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发表于 2004-10-4 02:55 |只看该作者 |倒序浏览

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<

>函数名: sbrk 
功能: 改变数据段空间位置
用法: char *sbrk(int incr);
程序例: 
<

>#include <STDIO.H>
#include <ALLOC.H>
<

>int main(void)
{
printf("Changing allocation with sbrk()\n");
printf("Before sbrk() call: %lu bytes free\n",
(unsigned long) coreleft());
sbrk(1000);
printf(" After sbrk() call: %lu bytes free\n",
(unsigned long) coreleft());
return 0;
}


<

>函数名: scanf 
功能: 执行格式化输入
用法: int scanf(char *format[,argument,...]);
程序例: 
<

>#include <STDIO.H>
#include <CONIO.H>
<

>int main(void)
{
char label[20];
char name[20];
int entries = 0;
int loop, age;
double salary; 
<

>struct Entry_struct
{
char name[20];
int age;
float salary;
} entry[20]; 
<

>/* Input a label as a string of characters restricting to 20 characters */
printf("\n\nPlease enter a label for the chart: ");
scanf("%20s", label);
fflush(stdin); /* flush the input stream in case of bad input */ 
<

>/* Input number of entries as an integer */
printf("How many entries will there be? (less than 20) ");
scanf("%d", &entries);
fflush(stdin); /* flush the input stream in case of bad input */ 
<

>/* input a name restricting input to only letters upper or lower case */
for (loop=0;loop<ENTRIES;++LOOP)
{
printf("Entry %d\n", loop);
printf(" Name : ");
scanf("%[A-Za-z]", entry[loop].name);
fflush(stdin); /* flush the input stream in case of bad input */ 
<

>/* input an age as an integer */
printf(" Age : ");
scanf("%d", &entry[loop].age);
fflush(stdin); /* flush the input stream in case of bad input */ 
<

>/* input a salary as a float */
printf(" Salary : ");
scanf("%f", &entry[loop].salary);
fflush(stdin); /* flush the input stream in case of bad input */
} 
<

>/* Input a name, age and salary as a string, integer, and double */
printf("\nPlease enter your name, age and salary\n");
scanf("%20s %d %lf", name, &age, &salary);

<

>/* Print out the data that was input */
printf("\n\nTable %s\n",label);
printf("Compiled by %s age %d $%15.2lf\n", name, age, salary);
printf("-----------------------------------------------------\n");
for (loop=0;loop<ENTRIES;++LOOP)
printf("%4d | %-20s | %5d | %15.2lf\n",
loop + 1,
entry[loop].name,
entry[loop].age,
entry[loop].salary);
printf("-----------------------------------------------------\n");
return 0;
}


<

>函数名: searchpath 
功能: 搜索DOS路径
用法: char *searchpath(char *filename);
程序例: 
<

>#include <STDIO.H>
#include <DIR.H>
<

>int main(void)
{
char *p; 
<

>/* Looks for TLINK and returns a pointer
to the path */
p = searchpath("TLINK.EXE");
printf("Search for TLINK.EXE : %s\n", p); 
<

>/* Looks for non-existent file */
p = searchpath("NOTEXIST.FIL");
printf("Search for NOTEXIST.FIL : %s\n", p); 
<

>return 0;
}


<

>函数名: sector 
功能: 画并填充椭圆扇区
用法: void far sector(int x, int y, int stangle, int endangle);
程序例: 
<

>#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
<

>int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int midx, midy, i;
int stangle = 45, endangle = 135;
int xrad = 100, yrad = 50; 
<

>/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
<

>/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("

ress any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
<

>midx = getmaxx() / 2;
midy = getmaxy() / 2; 
<

>/* loop through the fill patterns */
for (i=EMPTY_FILL; i<USER_FILL; {
/* set the fill style */
setfillstyle(i, getmaxcolor()); 
<

>/* draw the sector slice */
sector(midx, midy, stangle, endangle, xrad, yrad); 
<

>getch();
} 
/* clean up */
closegraph();
return 0;
}

函数名: segread 
功能: 读段寄存器值
用法: void segread(struct SREGS *segtbl);
程序例: 
#include <STDIO.H>
#include <DOS.H>
int main(void)
{
struct SREGS segs; 
segread(&segs);
printf("Current segment register settings\n\n");
printf("CS: %X DS: %X\n", segs.cs, segs.ds);
printf("ES: %X SS: %X\n", segs.es, segs.ss); 
return 0;
} 


函数名: setactivepage 
功能: 设置图形输出活动页
用法: void far setactivepage(int pagenum);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* select a driver and mode that supports */
/* multiple pages. */
int gdriver = EGA, gmode = EGAHI, errorcode;
int x, y, ht; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
x = getmaxx() / 2;
y = getmaxy() / 2;
ht = textheight("W"); 
/* select the off screen page for drawing */
setactivepage(1); 
/* draw a line on page #1 */
line(0, 0, getmaxx(), getmaxy()); 
/* output a message on page #1 */
settextjustify(CENTER_TEXT, CENTER_TEXT);
outtextxy(x, y, "This is page #1:");
outtextxy(x, y+ht, "Press any key to halt:"); 
/* select drawing to page #0 */
setactivepage(0); 
/* output a message on page #0 */
outtextxy(x, y, "This is page #0.");
outtextxy(x, y+ht, "Press any key to view page #1:");
getch(); 
/* select page #1 as the visible page */
setvisualpage(1); 
/* clean up */
getch();
closegraph();
return 0;
}


函数名: setallpallette 
功能: 按指定方式改变所有的调色板颜色
用法: void far setallpallette(struct palette, far *pallette);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
struct palettetype pal;
int color, maxcolor, ht;
int y = 10;
char msg[80]; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
maxcolor = getmaxcolor();
ht = 2 * textheight("W"); 
/* grab a copy of the palette */
getpalette(&pal); 
/* display the default palette colors */
for (color=1; color<=maxcolor; color++)
{
setcolor(color);
sprintf(msg, "Color: %d", color);
outtextxy(1, y, msg);
y += ht;
} 
/* wait for a key */
getch(); 
/* black out the colors one by one */
for (color=1; color<=maxcolor; color++)
{
setpalette(color, BLACK);
getch();
} 
/* restore the palette colors */
setallpalette(&pal); 
/* clean up */
getch();
closegraph();
return 0;
}


函数名: setaspectratio 
功能: 设置图形纵横比
用法: void far setaspectratio(int xasp, int yasp);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int xasp, yasp, midx, midy; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
midx = getmaxx() / 2;
midy = getmaxy() / 2;
setcolor(getmaxcolor()); 
/* get current aspect ratio settings */
getaspectratio(&xasp, &yasp); 
/* draw normal circle */
circle(midx, midy, 100);
getch(); 
/* claer the screen */
cleardevice(); 
/* adjust the aspect for a wide circle */
setaspectratio(xasp/2, yasp);
circle(midx, midy, 100);
getch(); 
/* adjust the aspect for a narrow circle */
cleardevice();
setaspectratio(xasp, yasp/2);
circle(midx, midy, 100); 
/* clean up */
getch();
closegraph();
return 0;
}


函数名: setbkcolor 
功能: 用调色板设置当前背景颜色
用法: void far setbkcolor(int color);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* select a driver and mode that supports */
/* multiple background colors. */
int gdriver = EGA, gmode = EGAHI, errorcode;
int bkcol, maxcolor, x, y;
char msg[80]; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
/* maximum color index supported */
maxcolor = getmaxcolor(); 
/* for centering text messages */
settextjustify(CENTER_TEXT, CENTER_TEXT);
x = getmaxx() / 2;
y = getmaxy() / 2; 
/* loop through the available colors */
for (bkcol=0; bkcol<=maxcolor; bkcol++)
{
/* clear the screen */
cleardevice(); 
/* select a new background color */
setbkcolor(bkcol); 
/* output a messsage */
if (bkcol == WHITE)
setcolor(EGA_BLUE);
sprintf(msg, "Background color: %d", bkcol);
outtextxy(x, y, msg);
getch();
} 
/* clean up */
closegraph();
return 0;
} 


函数名: setblock 
功能: 修改先前已分配的DOS存储段大小
用法: int setblock(int seg, int newsize);
程序例: 
#include <DOS.H>
#include <ALLOC.H>
#include <STDIO.H>
#include <STDLIB.H>
int main(void)
{
unsigned int size, segp;
int stat; 
size = 64; /* (64 x 16) = 1024 bytes */
stat = allocmem(size, &segp);
if (stat == -1)
printf("Allocated memory at segment: %X\n", segp);
else
{
printf("Failed: maximum number of paragraphs available is %d\n",
stat);
exit(1);
} 
stat = setblock(segp, size * 2);
if (stat == -1)
printf("Expanded memory block at segment: %X\n", segp);
else
printf("Failed: maximum number of paragraphs available is %d\n",
stat); 
freemem(segp); 
return 0;
}


函数名: setbuf 
功能: 把缓冲区与流相联
用法: void setbuf(FILE *steam, char *buf);
程序例: 
#include <STDIO.H>
/* BUFSIZ is defined in stdio.h */
char outbuf[BUFSIZ]; 
int main(void)
{
/* attach a buffer to the standard output stream */
setbuf(stdout, outbuf); 
/* put some characters into the buffer */
puts("This is a test of buffered output.\n\n");
puts("This output will go into outbuf\n");
puts("and won't appear until the buffer\n");
puts("fills up or we flush the stream.\n"); 
/* flush the output buffer */
fflush(stdout); 
return 0;
}


函数名: setcbrk
功能: 设置Control-break
用法: int setcbrk(int value);
程序例: 
#include <DOS.H>
#include <CONIO.H>
#include <STDIO.H>
int main(void)
{
int break_flag; 
printf("Enter 0 to turn control break off\n");
printf("Enter 1 to turn control break on\n"); 
break_flag = getch() - 0; 
setcbrk(break_flag); 
if (getcbrk())
printf("Cntrl-brk flag is on\n");
else
printf("Cntrl-brk flag is off\n");
return 0;
}



函数名: setcolor
功能: 设置当前画线颜色
用法: void far setcolor(int color);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* select a driver and mode that supports */
/* multiple drawing colors. */
int gdriver = EGA, gmode = EGAHI, errorcode;
int color, maxcolor, x, y;
char msg[80]; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
/* maximum color index supported */
maxcolor = getmaxcolor(); 
/* for centering text messages */
settextjustify(CENTER_TEXT, CENTER_TEXT);
x = getmaxx() / 2;
y = getmaxy() / 2; 
/* loop through the available colors */
for (color=1; color<=maxcolor; color++)
{
/* clear the screen */
cleardevice(); 
/* select a new background color */
setcolor(color); 
/* output a messsage */
sprintf(msg, "Color: %d", color);
outtextxy(x, y, msg);
getch();
} 
/* clean up */
closegraph();
return 0;
}


函数名: setdate 
功能: 设置DOS日期
用法: void setdate(struct date *dateblk);
程序例: 
#include <STDIO.H>
#include <PROCESS.H>
#include <DOS.H>
int main(void)
{
struct date reset;
struct date save_date; 
getdate(&save_date);
printf("Original date:\n");
system("date"); 
reset.da_year = 2001;
reset.da_day = 1;
reset.da_mon = 1;
setdate(&reset); 
printf("Date after setting:\n");
system("date"); 
setdate(&save_date);
printf("Back to original date:\n");
system("date"); 
return 0;
}


函数名: setdisk 
功能: 设置当前磁盘驱动器
用法: int setdisk(int drive);
程序例: 
#include <STDIO.H>
#include <DIR.H>
int main(void)
{
int save, disk, disks; 
/* save original drive */
save = getdisk(); 
/* print number of logic drives */
disks = setdisk(save);
printf("%d logical drives on the system\n\n", disks); 
/* print the drive letters available */
printf("Available drives:\n");
for (disk = 0;disk < 26;++disk)
{
setdisk(disk);
if (disk == getdisk())
printf("%c: drive is available\n", disk + 'a');
}
setdisk(save); 
return 0;
} 


函数名: setdta 
功能: 设置磁盘传输区地址
用法: void setdta(char far *dta);
程序例: 
#include <PROCESS.H>
#include <STRING.H>
#include <STDIO.H>
#include <DOS.H>
int main(void)
{
char line[80], far *save_dta;
char buffer[256] = "SETDTA test!";
struct fcb blk;
int result; 
/* get new file name from user */
printf("Enter a file name to create:");
gets(line); 
/* parse the new file name to the dta */
parsfnm(line, &blk, 1);
printf("%d %s\n", blk.fcb_drive, blk.fcb_name); 
/* request DOS services to create file */
if (bdosptr(0x16, &blk, 0) == -1)
{
perror("Error creating file");
exit(1);
} 
/* save old dta and set new dta */
save_dta = getdta();
setdta(buffer); 
/* write new records */
blk.fcb_recsize = 256;
blk.fcb_random = 0L;
result = randbwr(&blk, 1);
printf("result = %d\n", result); 
if (!result)
printf("Write OK\n");
else
{
perror("Disk error");
exit(1);
} 
/* request DOS services to close the file */
if (bdosptr(0x10, &blk, 0) == -1)
{
perror("Error closing file");
exit(1);
} 
/* reset the old dta */
setdta(save_dta);
return 0;
}


函数名: setfillpattern 
功能: 选择用户定义的填充模式
用法: void far setfillpattern(char far *upattern, int color);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int maxx, maxy; 
/* a user defined fill pattern */
char pattern[8] = {0x00, 0x70, 0x20, 0x27, 0x24, 0x24, 0x07, 0x00}; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
maxx = getmaxx();
maxy = getmaxy();
setcolor(getmaxcolor()); 
/* select a user defined fill pattern */
setfillpattern(pattern, getmaxcolor()); 
/* fill the screen with the pattern */
bar(0, 0, maxx, maxy); 
/* clean up */
getch();
closegraph();
return 0;
}


函数名: setfillstyle 
功能: 设置填充模式和颜色
用法: void far setfillstyle(int pattern, int color);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STRING.H>
#include <STDIO.H>
#include <CONIO.H>
/* the names of the fill styles supported */
char *fname[] = { "EMPTY_FILL",
"SOLID_FILL",
"LINE_FILL",
"LTSLASH_FILL",
"SLASH_FILL",
"BKSLASH_FILL",
"LTBKSLASH_FILL",
"HATCH_FILL",
"XHATCH_FILL",
"INTERLEAVE_FILL",
"WIDE_DOT_FILL",
"CLOSE_DOT_FILL",
"USER_FILL"
}; 
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int style, midx, midy;
char stylestr[40]; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
midx = getmaxx() / 2;
midy = getmaxy() / 2; 
for (style = EMPTY_FILL; style < USER_FILL; style++)
{
/* select the fill style */
setfillstyle(style, getmaxcolor()); 
/* convert style into a string */
strcpy(stylestr, fname[style]); 
/* fill a bar */
bar3d(0, 0, midx-10, midy, 0, 0); 
/* output a message */
outtextxy(midx, midy, stylestr); 
/* wait for a key */
getch();
cleardevice();
} 
/* clean up */
getch();
closegraph();
return 0;
} 


函数名: setftime 
功能: 设置文件日期和时间
用法: int setftime(int handle, struct ftime *ftimep);
程序例: 
#include <STDIO.H>
#include <PROCESS.H>
#include <FCNTL.H>
#include <IO.H>
int main(void)
{
struct ftime filet;
FILE *fp; 
if ((fp = fopen("TEST.$$$", "w")) == NULL)
{
perror("Error:");
exit(1);
} 
fprintf(fp, "testing...\n"); 
/* load ftime structure with new time and date */
filet.ft_tsec = 1;
filet.ft_min = 1;
filet.ft_hour = 1;
filet.ft_day = 1;
filet.ft_month = 1;
filet.ft_year = 21; 
/* show current directory for time and date */
system("dir TEST.$$$"); 
/* change the time and date stamp*/
setftime(fileno(fp), &filet); 
/* close and remove the temporary file */
fclose(fp); 
system("dir TEST.$$$"); 
unlink("TEST.$$$");
return 0;
}


函数名: setgraphbufsize 
功能: 改变内部图形缓冲区的大小
用法: unsigned far setgraphbufsize(unsigned bufsize);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
#define BUFSIZE 1000 /* internal graphics buffer size */ 
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int x, y, oldsize;
char msg[80]; 
/* set the size of the internal graphics buffer */
/* before making a call to initgraph. */
oldsize = setgraphbufsize(BUFSIZE); 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
x = getmaxx() / 2;
y = getmaxy() / 2; 
/* output some messages */
sprintf(msg, "Graphics buffer size: %d", BUFSIZE);
settextjustify(CENTER_TEXT, CENTER_TEXT);
outtextxy(x, y, msg);
sprintf(msg, "Old graphics buffer size: %d", oldsize);
outtextxy(x, y+textheight("W"), msg); 
/* clean up */
getch();
closegraph();
return 0;
}


函数名: setgraphmode 
功能: 将系统设置成图形模式且清屏
用法: void far setgraphmode(int mode);
程序例:

#include <STDLIB.H>
#include <STDIO.H>
#include <GRAPHICS.H>#include <CONIO.H>
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int x, y; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
x = getmaxx() / 2;
y = getmaxy() / 2; 
/* output a message */
settextjustify(CENTER_TEXT, CENTER_TEXT);
outtextxy(x, y, "Press any key to exit graphics:");
getch(); 
/* restore system to text mode */
restorecrtmode();
printf("We're now in text mode.\n");
printf("Press any key to return to graphics mode:");
getch(); 
/* return to graphics mode */
setgraphmode(getgraphmode()); 
/* output a message */
settextjustify(CENTER_TEXT, CENTER_TEXT);
outtextxy(x, y, "We're back in graphics mode.");
outtextxy(x, y+textheight("W"), "Press any key to halt:"); 
/* clean up */
getch();
closegraph();
return 0;
}


函数名: setjmp 
功能: 非局部转移
用法: int setjmp(jmp_buf env);
程序例: 
#include <STDIO.H>
#include <PROCESS.H>
#include <SETJMP.H>
void subroutine(void); 
jmp_buf jumper; 
int main(void)
{
int value; 
value = setjmp(jumper);
if (value != 0)
{
printf("Longjmp with value %d\n", value);
exit(value);
}
printf("About to call subroutine ... \n");
subroutine();
return 0;
} 
void subroutine(void)
{
longjmp(jumper,1);
}


函数名: setlinestyle 
功能: 设置当前画线宽度和类型
用法: void far setlinestyle(int linestype, unsigned upattern);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STRING.H>
#include <STDIO.H>
#include <CONIO.H>
/* the names of the line styles supported */
char *lname[] = {
"SOLID_LINE",
"DOTTED_LINE",
"CENTER_LINE",
"DASHED_LINE",
"USERBIT_LINE"
}; 
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode; 
int style, midx, midy, userpat;
char stylestr[40]; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
midx = getmaxx() / 2;
midy = getmaxy() / 2; 
/* a user defined line pattern */
/* binary: "0000000000000001" */
userpat = 1; 
for (style=SOLID_LINE; style<=USERBIT_LINE; style++)
{
/* select the line style */
setlinestyle(style, userpat, 1); 
/* convert style into a string */
strcpy(stylestr, lname[style]); 
/* draw a line */
line(0, 0, midx-10, midy); 
/* draw a rectangle */
rectangle(0, 0, getmaxx(), getmaxy()); 
/* output a message */
outtextxy(midx, midy, stylestr); 
/* wait for a key */
getch();
cleardevice();
} 
/* clean up */
closegraph();
return 0;
} 


函数名: setmem 
功能: 存值到存储区
用法: void setmem(void *addr, int len, char value);
程序例: 
#include <STDIO.H>
#include <ALLOC.H>
#include <MEM.H>
int main(void)
{
char *dest; 
dest = calloc(21, sizeof(char));
setmem(dest, 20, 'c');
printf("%s\n", dest); 
return 0;
} 


函数名: setmode 
功能: 设置打开文件方式
用法: int setmode(int handle, unsigned mode);
程序例: 
#include <STDIO.H>
#include <FCNTL.H>
#include <IO.H>
int main(void)
{
int result; 
result = setmode(fileno(stdprn), O_TEXT);
if (result == -1)
perror("Mode not available\n");
else
printf("Mode successfully switched\n");
return 0;
}



函数名: setpalette 
功能: 改变调色板的颜色
用法: void far setpalette(int index, int actural_color);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int color, maxcolor, ht;
int y = 10;
char msg[80]; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
maxcolor = getmaxcolor();
ht = 2 * textheight("W"); 
/* display the default colors */
for (color=1; color<=maxcolor; color++)
{
setcolor(color);
sprintf(msg, "Color: %d", color);
outtextxy(1, y, msg);
y += ht;
} 
/* wait for a key */
getch(); 
/* black out the colors one by one */
for (color=1; color<=maxcolor; color++)
{
setpalette(color, BLACK);
getch();
} 
/* clean up */
closegraph();
return 0;
}


函数名: setrgbpalette 
功能: 定义IBM8514图形卡的颜色
用法: void far setrgbpalette(int colornum, int red, int green, int blue);
程序例: 
#include <GRAPHICS.H>
#include <STDLIB.H>
#include <STDIO.H>
#include <CONIO.H>
int main(void)
{
/* select a driver and mode that supports the use */
/* of the setrgbpalette function. */
int gdriver = VGA, gmode = VGAHI, errorcode;
struct palettetype pal;
int i, ht, y, xmax; 
/* initialize graphics and local variables */
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */
errorcode = graphresult();
if (errorcode != grOk) /* an error occurred */
{
printf("Graphics error: %s\n", grapherrormsg(errorcode));
printf("Press any key to halt:");
getch();
exit(1); /* terminate with an error code */
} 
/* grab a copy of the palette */
getpalette(&pal); 
/* create gray scale */
for (i=0; i<PAL.SIZE; setrgbpalette(pal.colors, i*4, i*4, i*4); 0 c7 s9 L# ?8 S( N6 {# @
/* display the gray scale */
3 o+ M+ ?1 E, a% z. I* W, Zht = getmaxy() / 16; 2 @% L2 ]$ s8 _
xmax = getmaxx();
5 X2 G& B, C4 m1 U/ u. r3 Gy = 0;
( Z& o8 c7 `8 _/ ^+ c P$ Gfor (i=0; i<PAL.SIZE; {
2 D& q3 p1 R n# q9 Asetfillstyle(SOLID_FILL, i);
& ]7 T3 y8 L0 v. _) e! R+ ^bar(0, y, xmax, y+ht);
; P5 d4 [6 m2 {, |3 fy += ht;
$ h- j5 p5 {# s/ b/ ~/ F% n5 S} / ?+ k2 ?* ~1 m8 ^
/* clean up */ 0 c/ r# Y$ D! k$ x
getch(); - a# x3 ^& }/ }4 w
closegraph();
# U) B8 _8 P% }1 W8 _1 ^- u' N1 xreturn 0; " |: E4 z+ I& L
}
9 a. s( j5 b6 F' h \. f
# B1 ]3 l2 j! z5 D! C; m- O+ A! P8 q
 B5 E3 D- e4 s9 }, x! O
函数名: settextjustify 
3 }; |$ l* A1 n% u1 i( q功能: 为图形函数设置文本的对齐方式 $ O6 A/ X+ K+ X( q$ U
用法: void far settextjustify(int horiz, int vert); 9 D) f/ d4 ~8 k% n1 x( q! M* f
程序例: 
0 _ s& L# ]( c) R#include <GRAPHICS.H>
0 e: O* t) ]$ M7 U7 v: b: h#include <STDLIB.H>
7 Q5 ?, f0 ?- x1 F Z9 k! ]#include <STDIO.H>
5 S. E/ W- R5 J5 W" h5 {2 G#include <CONIO.H>; q6 l9 Z4 A" e" `1 O/ k; m$ ]
/* function prototype */
; Y0 Z/ a* X8 Rvoid xat(int x, int y); / v) b$ a5 H, K
/* horizontal text justification settings */
0 J r+ @, v8 V; J: R$ c9 p# k* gchar *hjust[] = { "LEFT_TEXT", 4 N3 d) ~7 R) \$ i/ _6 A
"CENTER_TEXT", 2 e, m7 J/ W2 j+ ?) S* m: Y' T
"RIGHT_TEXT"
6 P1 D4 J" c) h' N1 m" Q}; 
2 f: x' d8 q4 N; g- \- |# @ h$ b/* vertical text justification settings */ 5 i1 U# `: O' d
char *vjust[] = { "LEFT_TEXT",
" e8 S' J; ^1 d* }$ C4 {9 {: M"CENTER_TEXT",
! ]" L8 G& J6 Y' Y8 G7 L9 a"RIGHT_TEXT" 2 f6 F: l' l( k# T, @
}; 
/ m2 S& A+ J; t( Bint main(void)
) N. j: t2 g8 Z9 w H& n{
. j) @" ?3 }0 z% z! _ S& x/* request auto detection */ 0 E: {3 ^- l+ z
int gdriver = DETECT, gmode, errorcode;
1 P. m! K; L5 S' u L r3 {* Uint midx, midy, hj, vj;
8 M8 M; J8 q( d) ]! g5 c1 V) Schar msg[80]; 
# Y0 Z6 z* ~+ M. u( N1 t/* initialize graphics and local variables */ 5 u: H8 G! \( I6 s
initgraph(&gdriver, &gmode, ""); + }7 v9 n2 ~* L o/ j
/* read result of initialization */
" x. Y2 ~. G2 ?errorcode = graphresult();
* R/ v" J; h4 D' i# @, A2 n- Z. r) rif (errorcode != grOk) /* an error occurred */ , F( Q6 L3 Z, U1 _) i3 H8 [5 z8 ]. v
{ 1 Z& c9 K) J' H4 q$ U
printf("Graphics error: %s\n", grapherrormsg(errorcode));
, A: I# V8 d% A/ r1 N6 dprintf("Press any key to halt:"); ) C, v! R( \+ ^6 U
getch(); - R! g* b) m# s+ j: q
exit(1); /* terminate with an error code */
, o+ ~3 r, }4 x} ; B( R6 \7 E- A
midx = getmaxx() / 2;
& M' O3 R0 n+ `8 X7 E" Vmidy = getmaxy() / 2; 
& i) D( o7 c: P6 F6 k' d/* loop through text justifications */
/ z/ ^2 |% f1 I$ R* b1 U- vfor (hj=LEFT_TEXT; hj<=RIGHT_TEXT; hj++)
- E% m% T; V. M% B, K9 a. [ Wfor (vj=LEFT_TEXT; vj<=RIGHT_TEXT; vj++)
7 M0 H7 n2 z' Q{
) E% x/ J. R* c/ y: P3 Xcleardevice();
! G( M' S6 T" ~5 C/* set the text justification */ : ?- R' l8 o% Y& F3 D' l4 a6 y5 Q
settextjustify(hj, vj); ) I% m6 B: J _2 C% H; v* O
/* create a message string */
8 E( @8 h+ {; @sprintf(msg, "%s %s", hjust[hj], vjust[vj]); 5 O2 a3 r& @" Y% Q, k4 l
/* create cross hairs on the screen */ 5 M r* H4 V# m: n; M
xat(midx, midy); 
6 b+ H q9 K- ]4 q q/* output the message */
2 `" o2 o# p$ d- y0 C9 Mouttextxy(midx, midy, msg);
2 b9 ]0 H3 c, f; igetch(); 7 Y( r0 B2 g8 d! m5 m& u& W$ M
} " M1 Q1 e1 { I$ |1 W
/* clean up */ ( z; i: G3 ]" J! V: G+ I9 F; x
closegraph();
( Y0 a9 {/ f" _( rreturn 0; 2 U8 x# G( g# B7 D) N! ~. Y( R7 S, P
} 
; s7 s: U, A# y$ W/* draw an "x" at (x, y) */
) I# n- u! j2 Y, Nvoid xat(int x, int y) 6 k1 Q6 [- l, b8 T
{
: v2 c9 U z9 |3 a& |" u, C0 m' Wline(x-4, y, x+4, y);
; y) E% m8 B# D4 S) s4 e, Lline(x, y-4, x, y+4);
" D4 e: n6 G$ F6 E) b} 2 \: s6 o* e0 o4 k7 R' \0 _

+ q% U6 E: v9 l6 W0 O+ h: A W% r$ f! v g3 w- P4 p
函数名: settextstyle 
6 @& v1 ~4 }! m M( |* K功能: 为图形输出设置当前的文本属性 % h4 y5 j L4 W5 p
用法: void far settextstyle (int font, int direction, char size);
+ I5 U( Z6 w$ \程序例: ; ?. x+ w0 a3 l
#include <GRAPHICS.H>
1 |- Q5 ~/ | U* B#include <STDLIB.H>
+ j/ A N7 ^. O#include <STDIO.H>
/ N A# B; f3 G {, ~" ~- B. t#include <CONIO.H>
) y7 v/ @$ F; \; T( W/* the names of the text styles supported */
 s% ~1 X& a4 L& t# Y6 O5 `3 @char *fname[] = { "DEFAULT font",
* o! ?5 i! f F! b9 {"TRIPLEX font", - v4 D/ L0 t( Z5 V
"SMALL font",
0 H; o: \2 A8 o6 m1 r$ I"SANS SERIF font",
! K% Z3 y# _5 e- V& H6 A& z"GOTHIC font" # }2 U# d8 o! g9 \3 h
}; 
' ?: v0 ?( ~7 }; }0 Mint main(void) 9 @( p _2 T" Z; U/ X2 N/ F2 g7 R
{ # h6 S; b6 k6 R
/* request auto detection */ 7 E5 M* {8 D9 W0 W* ]; S
int gdriver = DETECT, gmode, errorcode; * D2 `) B$ k# J& S7 o
int style, midx, midy;
" j& _$ b& ?- ?1 s* Y; m& r; Z! \int size = 1; 1 I: U6 g8 z! k! s4 @# M
/* initialize graphics and local variables */
8 Q/ F5 B* [: h2 Z# Hinitgraph(&gdriver, &gmode, ""); 
0 z i. @. Y& h* O6 G/* read result of initialization */
4 @2 [, p5 T+ t) [7 Rerrorcode = graphresult();
, \ j/ o- E6 I' Cif (errorcode != grOk) /* an error occurred */ ' F( F. l6 H5 Y. u6 ^; _
{
; j8 ^* a& h3 K5 h0 P: ^printf("Graphics error: %s\n", grapherrormsg(errorcode)); 6 ^. G5 v4 b) b% L! i* |; P$ a/ s
printf("Press any key to halt:"); 4 g# c8 a# `. k% a& _! ~( ^7 M
getch(); 0 ?$ ~0 @7 ]' ^ i9 N% A" Z, h
exit(1); /* terminate with an error code */ " |6 R( A. |" P6 \9 I, \/ G# H; m" l
} 
( z, d7 f* Q% ?/ c/ e9 ] ?- H0 hmidx = getmaxx() / 2; / u4 e; n/ l9 A) C% q/ L' w8 d
midy = getmaxy() / 2; 
9 |8 q. L8 x! T) ~# V$ Psettextjustify(CENTER_TEXT, CENTER_TEXT); 
# x5 g' u# Z/ R, E/* loop through the available text styles */
2 k$ `- k" C+ v9 _+ U i6 Z& zfor (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++)
7 a3 y, O# G! A3 \0 R$ F0 }- w{
8 r; g! d* }# Q+ L% ocleardevice();
 P( a+ ]& k8 Z6 N: rif (style == TRIPLEX_FONT) ' B/ f3 t5 l: \6 } J0 a5 `2 |/ i
size = 4; 1 D1 k, |' a' A( }' f
/* select the text style */ 2 j! S) Z7 \7 _6 P0 W
settextstyle(style, HORIZ_DIR, size); ) U1 E6 ~4 O) j0 N3 b; a9 H, ]
/* output a message */
7 a' V& E( _% ~7 e- mouttextxy(midx, midy, fname[style]); ) |1 e1 n8 K5 K% F
getch();
4 U) a8 }) |! q" I9 T5 s8 S} 
 i- z3 R! K6 N7 w/* clean up */ + V5 O% z, M f+ i% {" u
closegraph(); " I. _" l9 X7 K1 j, O
return 0;
9 m2 ?0 T; X7 T- k: L}
8 ?' Y: ]- _6 o% L, x
/ }! {/ J3 O' J+ ~0 D
" ^$ a8 @7 W) I4 a: v& }函数名: settextstyle 
5 k( u* [! I! t6 O3 l/ |- ^5 m: i功能: 为图形输出设置当前的文本属性
( \" x! x x7 o用法: void far settextstyle (int font, int direction, char size);
; A0 x0 S* i7 U6 f. _' w程序例: 
) y3 I% F. K3 R4 W2 |& B#include <GRAPHICS.H>9 S& [' |0 v. K) E3 N
#include <STDLIB.H>
$ X! d0 V$ J9 L" b1 M; ]#include <STDIO.H>
8 g$ L% Q3 d% G! T#include <CONIO.H>
( n1 }/ |2 }$ E& Z7 ^2 |9 |" l/* the names of the text styles supported */ ; R. q# J! P% `% P7 A1 z5 ?0 S
char *fname[] = { "DEFAULT font", # n7 k; {) B& w% g
"TRIPLEX font",
, m0 s% S$ Y( M2 U! x/ O2 K& r"SMALL font", 2 H8 B; C' j/ X9 l! X
"SANS SERIF font",
( X* ^/ `& a$ R; s"GOTHIC font" 4 _' @7 ^& o$ G, j; l8 T" ^
}; ) e8 ^- ^) {+ m
int main(void) - J# f" U2 G1 ~
{
# z! L/ w" I+ B$ w- E( S4 w' d/* request auto detection */
8 Q! ?: Y8 l4 t7 ~int gdriver = DETECT, gmode, errorcode;
; i, O6 Z( j: O' _! E% C+ L& S! N4 R& Xint style, midx, midy;
 \* D2 q2 ~6 u, _9 cint size = 1; ; C; u/ Z4 v7 Q1 p, g
/* initialize graphics and local variables */ % s8 I1 _; b# ?
initgraph(&gdriver, &gmode, ""); B) S9 n% v! t2 @& Q1 p$ { z0 I
/* read result of initialization */ $ X; o4 }5 J" R" n. r
errorcode = graphresult();
 z$ `' ~6 h% iif (errorcode != grOk) /* an error occurred */
4 {! B5 V1 r" J6 m g5 r{
# c+ W; Y+ q1 L7 ^printf("Graphics error: %s\n", grapherrormsg(errorcode)); 1 z* f4 }0 I* s. p6 A/ X
printf("Press any key to halt:"); : p! v0 Y1 j) [ x
getch();
+ l2 b! N4 U- F. D" cexit(1); /* terminate with an error code */ ( g6 Z' N. w. E( b# `9 I
} 5 v4 |! O" i4 ^4 o. [; x
midx = getmaxx() / 2;
! B; d5 `0 j0 e9 V" Y1 n7 {midy = getmaxy() / 2; 6 d/ ^# w9 b/ F% Z2 E% Q3 Q
settextjustify(CENTER_TEXT, CENTER_TEXT); 
- L" n$ @7 T5 a6 A3 Q6 r/* loop through the available text styles */
; \: {% Y- I* \1 V: p( w" wfor (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++)
, h) x S3 M& k{ e8 R8 Y; L' y" @
cleardevice();
* Z: A* x* C0 }" w% Wif (style == TRIPLEX_FONT)
0 l7 v* }6 Y/ G' K% {* s- Zsize = 4; 
$ ~; M& |! T5 g: ]* g4 p/* select the text style */
, [) `+ F( `0 Z O0 Wsettextstyle(style, HORIZ_DIR, size); 
/ @9 `% f" Q2 l' Y2 c' L% ?6 v) \/* output a message */ 2 \; x4 n5 R/ Z; `
outtextxy(midx, midy, fname[style]);
2 r3 r! M3 S egetch(); 3 z/ L! W4 R& j
} 6 }! o3 D$ y ]0 v O
/* clean up */
# q2 y1 [% s" {0 ]- }9 o& @- h& Zclosegraph(); ' _$ \- F2 N$ B! W7 O) q
return 0;
2 a" n5 l8 K! `& V5 s9 p} 
. U0 G0 L3 e- f4 n& K2 h' D Q4 }( S9 H; o" n- n

! ?. }9 o0 X4 J+ r) G$ B6 I9 M4 G" L函数名: settime 
; f+ a; n2 J) }6 n/ P1 X功能: 设置系统时间
- @3 X2 U. [; ]& p+ q2 t用法: void settime(struct time *timep);
# s3 P/ Q* k1 d0 k" B程序例: ' ~ G: E9 h: m$ s& P2 P" z7 F
#include <STDIO.H>
' a- U5 Q% Z4 ?5 W1 J' f0 D#include <DOS.H>
0 F& a8 t0 F; f3 tint main(void) - f6 S ~) O5 t* _* }
{
! F+ `" t4 X& z3 }) tstruct time t; " d7 T6 g: r4 p" N, v% s
gettime(&t);
2 w5 v( f; G% W9 I4 {8 y. P5 Cprintf("The current minute is: %d\n", t.ti_min);
2 }" o# ~0 B% y }6 X8 uprintf("The current hour is: %d\n", t.ti_hour);
- D y1 p5 v pprintf("The current hundredth of a second is: %d\n", t.ti_hund); 6 a! X* L; k( g9 G: C, i: V
printf("The current second is: %d\n", t.ti_sec); 
3 z2 Z) B) s4 X( {" X/* Add one to the minutes struct element and then call settime */
9 n a7 g0 ?7 t' It.ti_min++; ! B/ b6 b( I0 n( ~! d
settime(&t); : @- Z% h' d S: T+ C
return 0; ! n, c# r: K) h3 e3 n: V' L# s9 S
} 3 ^6 O. R- X O/ @0 F( w! `9 f
! L' d; C1 m; K6 h; y! |
% S' ]7 b/ _3 l; ]/ P8 j2 J
函数名: setusercharsize ( E1 D. W2 F, s$ G
功能: 为矢量字体改变字符宽度和高度 - `% v: A% F( q
用法: void far setusercharsize(int multx, int dirx, int multy, int diry); 7 @3 ^5 y$ j0 b5 l# p k
程序例: 4 P; _( z/ U9 O8 o, u4 j/ x* F. l& c% _
#include <GRAPHICS.H>
6 e# n9 v7 w* Y$ p#include <STDLIB.H>7 Q% `: Z- C: o) B4 T! X t3 X9 D
#include <STDIO.H>
, w4 q# n. U+ h% G( o0 E0 h#include <CONIO.H>1 S; f: l' w5 z; G. h
int main(void)
% ]" E* s9 |$ _$ u- O1 o{
* |4 H" O4 S" @ Y/* request autodetection */
+ H5 m: D* Y1 _- M1 q" yint gdriver = DETECT, gmode, errorcode; . O4 s7 Q4 o5 ]: \ b7 x1 L: q7 @
/* initialize graphics and local variables */
7 Q+ a0 O+ j$ R" F" d0 y3 Cinitgraph(&gdriver, &gmode, ""); 
( c3 C) p. l: a8 A/* read result of initialization */
2 K8 A* D( ^) f8 E# berrorcode = graphresult();
- u" G1 G0 ]! \/ [9 O5 V$ Nif (errorcode != grOk) /* an error occurred */ , _- w: q3 A- M$ ?# g
{ ( z0 ~9 K* Y% n/ c
printf("Graphics error: %s\n", grapherrormsg(errorcode)); 5 I0 [# F- E4 q+ ]! K: `6 Y% |
printf("Press any key to halt:");
/ a& ^: G, U+ O! F, z* jgetch();
. t4 o( o# c0 [" \$ @exit(1); /* terminate with an error code */
. J+ J& _: _: \} 
6 X" r2 c" |' z! _4 a/* select a text style */ $ f/ A+ d2 D1 A- J7 G# {; x- _
settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4); 2 _/ R5 R' j4 w# T3 A
/* move to the text starting position */
& s8 Y3 [9 r/ _: \moveto(0, getmaxy() / 2); 
1 F+ h ]3 \3 M1 `: `" s% g/* output some normal text */ : q7 K+ l- T' c1 ]+ S; S
outtext("Norm "); 
8 t2 T0 Z3 ]$ m: R/* make the text 1/3 the normal width */ ; U6 L. F- @/ f( e
setusercharsize(1, 3, 1, 1);
/ `% T3 B1 R* q* [1 C9 Douttext("Short "); " Q! @+ {( P+ p0 w# ~5 ]
/* make the text 3 times normal width */ ; E4 M. z! k3 c3 D$ _9 ]7 f8 M
setusercharsize(3, 1, 1, 1);
 n7 R/ Y: M- u% Z' Z9 R8 o) ~4 h: Touttext("Wide"); 
$ p0 D, P0 i3 E0 a e/* clean up */
8 q1 y0 X" X9 A1 i5 ~1 s% v2 pgetch();
4 t0 [- e7 l7 x+ r( J5 m! P, W& Hclosegraph();
0 S' g& u9 A* q6 S) Areturn 0;
$ }2 A" p4 j, G1 u# E: s* ]; T R+ {} 
" r$ I! R8 w% Y0 `# `& T I# p9 k
" N8 D w% s# C) w函数名: setvbuf ( b/ O1 z/ V1 e2 @6 O8 s. e
功能: 把缓冲区与流相关
" z# O+ ?: J; O7 V. n/ y' T用法: int setvbuf(FILE *stream, char *buf, int type, unsigned size); - m) i% u; d3 z1 }( T- B
程序例: - r" I4 Z9 \) B
#include <STDIO.H>
5 @8 D# W+ V- R6 J# K9 `% Y9 cint main(void) 5 b% {. Y8 _ d5 g
{
* u/ d' S: N+ c9 c* K7 eFILE *input, *output;
 d! _* K& z! }$ \5 t/ d1 u* _5 ychar bufr[512]; 
+ q% w1 w3 ~* c! U8 `7 c# k# _2 ~2 Sinput = fopen("file.in", "r+b");
8 A, e, I0 c! T6 F, loutput = fopen("file.out", "w"); 
% X4 P* D5 x& l/* set up input stream for minimal disk access, 7 l4 F' x1 M$ A _* f- K2 ?
using our own character buffer */
/ R( u; @0 W3 N9 j) |if (setvbuf(input, bufr, _IOFBF, 512) != 0) " w4 i4 \: J) F4 f) O* L
printf("failed to set up buffer for input file\n"); 4 i" s9 ]1 p8 f
else
 {# D, q* ^4 p6 P9 ~: Z2 mprintf("buffer set up for input file\n"); 
& T/ v# W/ L" F/ o/* set up output stream for line buffering using space that
" u, P# ^/ ]( e. |& ywill be obtained through an indirect call to malloc */ , u1 j; [7 V) ^9 |$ q7 v
if (setvbuf(output, NULL, _IOLBF, 132) != 0) 5 |+ Q; U+ ?' |9 R9 y8 [
printf("failed to set up buffer for output file\n"); ) i: S( h# a7 ?7 I2 }$ n) u
else
$ J4 T9 j' [0 z+ b( @; _% Fprintf("buffer set up for output file\n"); 
$ h5 \% ~0 W( k/* perform file I/O here */ 
1 p+ G9 }! R+ }2 c0 l/* close files */ 0 E/ J" c( Q3 b# \8 o
fclose(input);
/ _9 B/ K6 \% p# b5 lfclose(output);
- J8 Y/ v& D3 y" \ treturn 0;
# w, J- P0 t; o} 1 C8 S9 x/ r! o9 [; C

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9 T) F9 J9 o: R, z1 R. f
- ~# I% A ^ K5 v函数名: setvect # q0 d+ R' [+ n5 T' @" w/ i
功能: 设置中断矢量入口 ! @- b* `5 {, g0 y9 s( O% u$ Q- Z: C
用法: void setvect(int intr_num, void interrupt(*isr)()); " x1 n: t0 n4 E* U, B$ i
程序例: * _9 Y( Y* W, S& N0 Z# W
/***NOTE: : Z J. I& D* @. q0 I" L* Y
This is an interrupt service routine. You can NOT compile this 7 v6 x/ U( Y3 z/ F1 w
program with Test Stack Overflow turned on and get an executable
( i. q6 W U5 {8 Z3 |/ r, Ufile which will operate correctly. */ ' j6 g9 G/ E9 b8 k; _2 e" d
#include <STDIO.H>) W! E% w0 g$ D% c- \
#include <DOS.H># Z& T; c4 ?8 C
#include <CONIO.H>& h% `/ `. _" {
#define INTR 0X1C /* The clock tick interrupt */ 6 M0 U+ D; Y7 |6 |3 U% J& Q: N
void interrupt ( *oldhandler)(void); 
7 O2 Q" _# S, s6 q* Qint count=0; 
0 Z( T+ B8 A- b! r0 j: D: rvoid interrupt handler(void)
$ T j, O6 o$ D/ H& F{ 7 j3 [- H8 C- k' `+ P
/* increase the global counter */ 5 i4 o2 i3 ^0 |2 h* \0 G
count++; % f) p! t; [' m2 e2 O# E
/* call the old routine */
1 V B4 H3 t: Y% `- ~# M) F ooldhandler();
/ L# T3 B! T- u. }0 x+ Y* d: v} 
 H7 x X+ a% A) a9 J! Uint main(void) % f: d0 f2 i" B
{
. L8 w8 _+ f& C0 `/ d3 c- j/* save the old interrupt vector */
( [+ o3 ~7 C% }) Voldhandler = getvect(INTR); 7 S) f1 `3 Z2 b) ~
/* install the new interrupt handler */
( f- a: p& x$ L9 X3 Hsetvect(INTR, handler); * u3 x* v- d: ~& N
/* loop until the counter exceeds 20 */
: O" d4 @! }. W7 t. Gwhile (count < 20)
8 t8 k$ `* Q* t+ @9 c0 e' P5 wprintf("count is %d\n",count); ; M5 @$ s( k- P: E i' r5 {
/* reset the old interrupt handler */
: w3 i8 z$ h* Y" n# t: _. v3 [setvect(INTR, oldhandler); ( i1 }( ~4 }# w5 E; \( R
return 0;
0 `0 S3 e# ]/ Q) `& u2 E}
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" F( l9 K d& X8 Q函数名: setverify 
/ e. D0 k, H. R: R* V功能: 设置验证状态 9 z5 q) Q1 Y. s+ {% \" v
用法: void setverify(int value);
9 z, q8 F6 P7 q: U# X( V程序例: . i$ R! c% b% c3 \
#include <STDIO.H># n! g' N! e$ w) }: y8 @/ }& ]
#include <CONIO.H>
* z% z" x; X4 e. f9 @#include <DOS.H>
6 {$ K; L+ T& M+ w6 B. ?int main(void)
9 `5 }$ U4 _* e- h{
: s- z0 E8 D6 {1 Nint verify_flag; 
% g, N# ~+ ], J7 jprintf("Enter 0 to set verify flag off\n");
0 U, V3 _- S |4 zprintf("Enter 1 to set verify flag on\n"); 
3 U8 Z5 b5 m: {" g' [7 j& Yverify_flag = getch() - 0; Q4 ^: }* g6 V, p f+ m
setverify(verify_flag); 
8 |6 p+ a9 ]9 \1 }if (getverify()) ) z! S4 F2 K: O, q9 `' s7 l+ |* Q1 A
printf("DOS verify flag is on\n");
4 e( f! J4 x: v6 |% t5 v& s" yelse
: u. d" r& _: k/ g- q4 t1 Eprintf("DOS verify flag is off\n"); 5 r; |1 R% z$ }! Y4 t
return 0;
) b7 x+ G# d; P' E s) o5 p' b} + V. m' V. g0 C. P& U$ Y) ^

2 t( m; ~* u! ]5 M! W" T
3 m8 t) F" q! ]: u1 |, h2 K+ |# B( c函数名: setviewport 
) l+ I3 o& E* a1 o9 S9 E功能: 为图形输出设置当前视口
4 K$ h# m1 N$ X用法: void far setviewport(int left, int top, int right, - {; t* Z, s) w7 B3 h n1 Q7 B
int bottom, int clipflag);
. Q! {) N# y7 B4 K# x0 X2 U程序例: 2 W$ f- c! Y5 q" I1 y. y7 ` b
#include <GRAPHICS.H>0 Q, n8 F$ N; N) x1 A* W
#include <STDLIB.H>) u8 p& j; V' P7 i" y3 G* C
#include <STDIO.H> |8 [+ M9 r" [: u
#include <CONIO.H>
#define CLIP_ON 1 /* activates clipping in viewport */ 
: t9 b3 o( `5 e5 ^int main(void)
. i9 |3 P% U7 h8 o5 X1 @2 }{ ! z3 L6 h7 ^7 d; h3 R$ z# S/ ^+ l" `: p* f
/* request auto detection */
/ @( O. y$ v: W3 M2 K9 \int gdriver = DETECT, gmode, errorcode; - _1 `' I9 v5 J' d+ I9 K: V
/* initialize graphics and local variables */
& }( N7 {9 s- T2 dinitgraph(&gdriver, &gmode, ""); 3 ]9 a3 A# v- b2 c X
/* read result of initialization */ $ ^3 h+ u! H$ Q* ^ L/ r3 |
errorcode = graphresult();
% v0 K* Y0 z1 ~if (errorcode != grOk) /* an error occurred */ 5 j" l8 C) T: t$ |1 ?$ G
{
! t, Z+ J; M& Vprintf("Graphics error: %s\n", grapherrormsg(errorcode));
6 E! _) L& r7 F* j' iprintf("Press any key to halt:");
$ V' ]+ L0 [) A' y7 E) v1 J0 v; Hgetch(); 9 Y' l* R! l/ `( R1 \
exit(1); /* terminate with an error code */
9 r, R6 v( _, l/ l- `3 |4 H} 
& w' ?5 X- q& [" h1 p8 o! isetcolor(getmaxcolor()); 7 a4 L$ t6 c! G! c9 l) [0 M
/* message in default full-screen viewport */ " U. y) R, B! @! L/ }
outtextxy(0, 0, "* <-- (0, 0) in default viewport"); 
% t: i" I9 ~* T5 {/* create a smaller viewport */ 7 b& E4 z& p1 K7 W: e- }
setviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON); ; z6 g: L3 G- e; W' H5 y6 L' h7 e! ]
/* display some text */
2 u' y* q# z5 ^1 Wouttextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 0 e! b3 @3 y5 i1 I) u
/* clean up */ 1 G0 c8 l* B4 _1 R' y+ N
getch();
8 G6 M. k5 R/ \# z8 F8 A" lclosegraph(); # E2 g! ] G% \+ X
return 0; 6 a p' [; U: S
}
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* k. p2 k, q5 n0 z( ^2 z- V6 {# h' @& e5 A6 X# F. n
函数名: setvisualpage + Q# K& W5 P x7 K& M; R
功能: 设置可见图形页号 : _& j W$ D# c& ~
用法: void far setvisualpage(int pagenum);
( X7 Q( W. x+ s/ ? @! m6 C9 C- I& O程序例: 
3 I& \# i. t4 D' L#include <GRAPHICS.H>5 q8 B' u6 o$ B6 m, M
#include <STDLIB.H>. G" h" E% I; V+ ~4 v' T
#include <STDIO.H>
, u, M8 s) r- ]4 V* G# n#include <CONIO.H>4 |) c! h, @- L; G s) }
int main(void)
" D& i8 U. p% ?; O6 W2 a# i{
4 [4 ]# q: C# i1 w/* select a driver and mode that supports */ 6 w: \: ~' a. e8 e ?2 [: F
/* multiple pages. */
; z7 @! N5 \' A# Fint gdriver = EGA, gmode = EGAHI, errorcode;
& S9 s/ Z. G) z cint x, y, ht; 
/ g1 t9 _0 h8 Z1 O4 x/* initialize graphics and local variables */ ; f2 I9 n. u: S l
initgraph(&gdriver, &gmode, ""); 6 U' p$ p+ q9 ], l& T6 \, b# m* F
/* read result of initialization */ ! |) l3 l1 L3 U0 d* a+ p# Y s* @; ?# a
errorcode = graphresult();
5 P, \ K- C. j8 G$ O: C; B/ j- Q) [if (errorcode != grOk) /* an error occurred */
0 `. ~$ ?, j+ v, z% [7 F8 q{
% f D/ c0 O/ ?! U- o# jprintf("Graphics error: %s\n", grapherrormsg(errorcode)); " e N3 n0 B: h8 M. n
printf("Press any key to halt:");
, G0 J x6 M( Dgetch();
0 @6 S( p! T J( P Gexit(1); /* terminate with an error code */
) v" Y1 u6 T# e3 L/ N# ~8 b. E} 
7 h8 M; d4 V4 [( m4 a3 Wx = getmaxx() / 2;
/ z8 }9 x! o( {4 g+ S! Wy = getmaxy() / 2;
* h! I% w- Y1 U- Z) {ht = textheight("W"); 
% k/ t9 Q/ `8 H, A" A" s/* select the off screen page for drawing */ ( t% H. Y9 v& x# Z, c5 T9 A% ~
setactivepage(1); # W V% D2 X& F; Q- ~: c
/* draw a line on page #1 */
7 l9 y! {( K lline(0, 0, getmaxx(), getmaxy()); 
& g2 Z( t& _1 F* V/* output a message on page #1 */ - w5 D: {& ^4 t2 I0 `1 J
settextjustify(CENTER_TEXT, CENTER_TEXT); ) F# K/ u# d' I3 T4 h
outtextxy(x, y, "This is page #1:"); , E6 r3 n) ^/ P2 S4 L
outtextxy(x, y+ht, "Press any key to halt:"); * Q. o6 k* o/ V6 x$ D
/* select drawing to page #0 */ ; P* c3 d% A* r' d3 W
setactivepage(0); - u/ p* Z4 w8 D2 g+ ^
/* output a message on page #0 */ / P: f/ B2 o) w2 T! I, K- ^ F# l# r
outtextxy(x, y, "This is page #0."); ' F' \% }* m1 Y2 N* ~- J. B
outtextxy(x, y+ht, "Press any key to view page #1:");
/ B& W* O% l1 i' D! mgetch(); 
( O3 B% Q3 G C# c' f/* select page #1 as the visible page */ 4 T T! u$ x V2 V: W( A' ?
setvisualpage(1); 
. j8 j+ k) [8 }& _( O3 S/* clean up */ ' [: f. V: J9 _; x
getch(); # s q* \1 \9 P0 h
closegraph(); % `& R8 |* S" M4 P d/ K7 p
return 0;
. i3 l: F3 z" n9 R& K* H} # x; Q3 u' ^/ d% N) U. H

8 ~/ {7 P0 d' c; d% t# W) s$ W: ]% o6 a. i
函数名: setwritemode 
) R% d) s" j5 l. o功能: 设置图形方式下画线的输出模式
0 w: v, ~9 Q/ C# |" ?9 h用法: void far setwritemode(int mode); 4 s; v( u1 [; F. x3 v* N0 P. a
程序例: 
3 c+ ?( f: |1 R; ]#include <GRAPHICS.H>2 R/ U4 r. i9 N1 G2 w
#include <STDLIB.H>
% O6 _; P) |: H#include <STDIO.H>
" o4 l3 O2 p+ ~; j. ~#include <CONIO.H>
& s/ l" K5 D) l g! o" b+ U9 ]int main() - e6 T, }( F2 A% r; B6 n
{ & g+ j7 v* P1 ]
/* request auto detection */
- G8 ~. b3 f- Z" }# Yint gdriver = DETECT, gmode, errorcode; ; }0 j: |# }1 _5 s; c7 s3 x
int xmax, ymax; 0 f0 d( w* m4 k3 J
/* initialize graphics and local variables */
5 P6 L" ^( ~ F, F: Yinitgraph(&gdriver, &gmode, ""); 6 R7 C6 l3 }# G8 W2 D1 e/ G- E' T, ~
/* read result of initialization */ ; W* W' M2 d9 S4 ]4 x# o
errorcode = graphresult(); {4 n; ?- m. E
if (errorcode != grOk) /* an error occurred */
! m- b& `4 y7 s9 m) w{ " W, R1 m$ c( A; @, J6 g, j
printf("Graphics error: %s\n", grapherrormsg(errorcode));
7 `. }8 @8 ]' F2 D. |' ] aprintf("Press any key to halt:"); 3 {8 O9 t( Y6 x' |! ?# B
getch();
! r0 N, @6 ~* c: X* B2 ~+ Vexit(1); /* terminate with an error code */
$ J% q4 j+ n0 U5 B} 7 v# q" r' @7 C$ R$ U5 b6 n' ?
xmax = getmaxx(); 8 N9 C3 k2 E7 U9 Y- M% a
ymax = getmaxy(); / {0 x1 Y h* N+ p! Q' T* \! L
/* select XOR drawing mode */
/ l- M" f* C9 D- ]setwritemode(XOR_PUT); 
5 e: u4 Q# C! q/* draw a line */ 4 f5 Q: F+ C& D: p. D6 W4 @
line(0, 0, xmax, ymax);
8 j4 F: W# x/ k) N6 |getch(); : m7 K9 o4 N3 k8 y# K7 q9 c4 T
/* erase the line by drawing over it */ @% o6 |( H. L% w" y( {6 G: X# I
line(0, 0, xmax, ymax);
5 S, {0 v' B* Ygetch(); 
: }6 o Q+ _1 a, q+ E0 k0 ^/* select overwrite drawing mode */ 6 u$ C& k* s1 P& K8 A6 P
setwritemode(COPY_PUT); 9 Y' l. s u, n/ n) W
/* draw a line */ + N. K5 l' [+ P3 x9 a
line(0, 0, xmax, ymax); 1 Q+ E& _5 n9 U1 r
/* clean up */ 1 Z0 H# E" ?9 D7 g# K. R
getch(); ) n; ^* d2 v% S4 e3 D
closegraph(); 0 o$ g5 I1 h3 I* q8 S5 L
return 0; : C! d0 ?( q/ A6 y2 p; `7 q& f$ H
}
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/ `! D2 O* A- c
, _. j2 @2 C- U4 Y函数名: signal
( B8 a1 N7 V4 z t功能: 设置某一信号的对应动作 ' x3 B+ }* `1 d6 g- J. ?
用法: int signal(int sig, sigfun fname); $ P; b! t9 s4 S! m* Y% ?
程序例: 
( r$ ]6 [/ l! C* M! H3 Z$ E. ~/* This example installs a signal handler routine for SIGFPE, " o9 {3 }& E9 _5 b6 W
catches an integer overflow condition, makes an adjustment ) Z% d8 n5 H+ A, v% @) W5 l
to AX register, and returns. This example program MAY cause ) Q9 X5 @4 B* }" ~; H6 a1 e1 y2 g9 [
your computer to crash, and will produce runtime errors " Y& O2 h6 q# k6 r
depending on which memory model is used. 7 b" I8 p7 x' {* N
*/ % Y3 O* l! }0 l h- o
#pragma inline
* d8 m0 Q6 S( {- W' V6 S: w) v7 V6 e#include <STDIO.H>
0 ^- k8 {5 }: b3 `1 m3 z#include <SIGNAL.H>
. `0 n( o+ \6 _' \/ p( v* Hvoid Catcher(int sig, int type, int *reglist)
1 Q3 M7 g& s) l" u{
3 @) V. r' Q8 D; k) lprintf("Caught it!\n");
. p! f% q# F! _, b*(reglist + 8) = 3; /* make return AX = 3 */
9 s4 W5 z. I( ]" a3 A' c} " `8 g: I* Q4 i" P( x9 G5 Z1 B
int main(void) % o" n' D) O! k k# ]: c
{ . K( g+ u6 g2 S- ?4 ]- q$ m, `
signal(SIGFPE, Catcher); , i D. k; u! I0 ]/ m5 g! b4 M
asm mov ax,07FFFH /* AX = 32767 */
- U, {' k! \* Y) Easm inc ax /* cause overflow */
2 M: \) m1 ?$ g8 Dasm into /* activate handler */ - C b4 y# a, l N+ _4 B
/* The handler set AX to 3 on return. If that hadn't happened, : k- K1 F/ B" j- J% g
there would have been another exception when the next 'into' : E$ K; M/ o+ I
was executed after the 'dec' instruction. */ ]1 I, h* I) X# K0 n: Q ?( i
asm dec ax /* no overflow now */ ; F0 J7 y. o$ g" r
asm into /* doesn't activate */
/ z' ~2 R7 Q( F: ^return 0; 6 ^) u) R9 j0 t2 L6 @
} 1 X/ }" d& Z3 M2 m

6 I2 Z; X& B) U/ b( K' I" n
% @# Y& p! ^/ W5 r; G7 }5 q
. Y( q! m0 n, @2 M% Z) t6 u6 y6 H+ u函数名: sin # d7 P0 e/ \$ |8 M; W4 i
功能: 正弦函数
* B4 ]/ M2 c2 ^& d6 H& }( H用法: double sin(double x); 9 P# r: A) r, c7 ]3 t! E& ?) I
程序例: 5 X: w7 j; G9 Y2 L
#include <STDIO.H>
+ N" @2 z; B0 f5 q2 M; k4 d V# Q#include <MATH.H>( K3 o- o/ z+ c
int main(void)
: x6 R2 X' R* B J: a9 g{ 8 W7 D3 P8 `/ [( ]( C' l
double result, x = 0.5; 5 f; g0 |2 |# A8 W. D6 O o
result = sin(x); . v7 R6 N7 a* v- z
printf("The sin() of %lf is %lf\n", x, result);
+ D) h/ E7 ^2 Y3 L, M, O- r4 creturn 0; # g. r) [( \ o& }' @4 i
} : u: H' T; J: E2 `6 s

, x. B+ [- k+ I* P, `* \) L& b2 ?
& \/ R+ w! ]4 b- e+ W! E函数名: sinh 
% r- H. ~. K+ j3 n! z功能: 双曲正弦函数
3 K9 ]* J- h/ y5 U7 F' T用法: double sinh(double x);
4 b" }0 F) a% E9 C4 _. x; m7 H/ x2 Y程序例: 
" x9 i: e7 F3 [/ Y#include <STDIO.H> B A+ B" r$ S% e3 M
#include <MATH.H>
! h7 B" z$ J1 @& M' Iint main(void)
3 L" V! l/ Q: p: _{
: r; F- F: M2 G4 f0 E. c. \/ A' S* Fdouble result, x = 0.5; 
5 \: v2 t X6 }: cresult = sinh(x); 9 B7 u0 e6 r. T% U
printf("The hyperbolic sin() of %lf is %lf\n", x, result); 1 `6 V3 U9 ]& t
return 0; / F: [+ _ a7 Z5 E
} v9 n `- O% u6 _" f
/ k% M8 u" K( l" S7 \9 a9 j9 Q

3 Z6 l1 `1 l7 ], X- t
' A& }* O: Z; U) L函数名: sleep 7 f# `- o& V6 P& d( `8 B9 O
功能: 执行挂起一段时间
! \) K0 Y5 s* T/ F5 [用法: unsigned sleep(unsigned seconds); 8 K! v1 k' l! [8 @7 Z
程序例: ! u( Y6 S) q- ~, B, X) s; T
#include <DOS.H>
, c3 }2 Q2 n, }- ^( | h9 R* ?#include <STDIO.H>
8 u" ~/ h$ _3 y8 S6 y: Z1 Dint main(void) 9 ~5 _, @$ i7 G5 G8 f( Z
{ + U" d1 P# C" U" @( g2 p
int i; 
! T& [* X4 ?; f: Nfor (i=1; i<5; i++)
- [( ?2 _) D/ ?# \. i! u) L7 l{ / \! X+ r' K, c
printf("Sleeping for %d seconds\n", i); " h' E6 X! B. B5 s$ D5 c
sleep(i);
4 r) ?! J2 E8 [} ' H# N5 t; Q- R/ ^1 k. S
return 0;
$ `' v: S+ @3 D v}
8 |- n$ ~9 ^: w4 \ v
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% A3 Q9 B# @6 ]7 T$ \- g/ _函数名: sopen 
' d% L+ N3 C, i! Q功能: 打开一共享文件
9 R, \3 I. S2 ~用法: int sopen(char *pathname, int access, int shflag, int permiss); " `7 N- i+ h5 H5 [: N I
程序例: ' O" J, L. o. d" ?+ Q( M
#include <IO.H>
% @# a2 O: |/ r+ C! @. H* Q% w#include <FCNTL.H>: V0 Z4 \+ \9 n. b: Q4 u" E- c
#include <SYS\STAT.H>- N4 E1 }+ ]0 m/ B" z' x5 ?( X
#include <PROCESS.H>* v" X; `/ T1 b, o" [3 a
#include <SHARE.H>
2 a, M. i5 D, b8 e5 \: c: t3 Z#include <STDIO.H>1 M) B* H/ @% K) e! [ I
int main(void)
# j/ |9 L- ~5 L" H4 j6 }4 s{
$ J* S' z$ E S F- O& fint handle;
# v3 G4 P& N4 v# I" _int status; # w, y' b Y# j4 w
handle = sopen("c:\\autoexec.bat", O_RDONLY, SH_DENYNO, S_IREAD); # A. s9 q4 t5 R* ~
if (!handle) / x6 ]! a5 B, w) m
{
6 C7 ]) h& x/ t6 n5 R# ?& @3 Yprintf("sopen failed\n");
. I6 z* {2 D2 P; Y( y6 }: h9 V3 rexit(1); " G' ~9 a7 k8 d! T: y, Z
} 
- t/ q) i. g/ q6 k$ Ystatus = access("c:\\autoexec.bat", 6);
0 M& A' m* t1 G$ k7 n& \if (status == 0)
! n: K# u2 X" T% U7 O3 Yprintf("read/write access allowed\n"); * l6 J5 a& r% V9 b, h# S( R
else U8 d# Z; Q* `" Z( d: [
printf("read/write access not allowed\n"); 
( I' e& F/ C. fclose(handle); - l' p2 e4 m, `0 v5 g
return 0; - y6 W8 |4 h. v6 z! c) o
}
+ U6 ?0 c* {3 H) L3 [: c
' @8 |% {" N, C. S
4 z: N: }& h; M: F( b5 r# K* a. D1 d) H
函数名: sound 
! m4 _$ E6 p* z3 p& I) E, {) m; }功能: 以指定频率打开PC扬声器 3 x4 k( _- {5 }$ T; r9 t: Z/ E
用法: void sound(unsigned frequency); 3 w: g3 P; A9 V; {$ w
程序例: 8 j% A- p! j5 g! I1 j' h( |
/* Emits a 7-Hz tone for 10 seconds. 4 u& R& N5 f# Q+ P3 Y
Your PC may not be able to emit a 7-Hz tone. */ $ c, u$ v: d+ u9 G5 z$ ` M
#include <DOS.H>
, K& u. X3 U* J0 }6 l$ jint main(void) 0 _+ g% [% n9 T* M
{
: _: g) S1 d- v/ z7 }sound(7);
" z7 ^7 T9 C2 L2 f, N6 Rdelay(10000);
2 }# P) z5 U* M9 G* ]nosound(); ; d+ Q0 i- U ]
return 0; ' m; T+ Z1 O+ @1 `
} 
- t7 ~& y+ {* c" O9 T( r$ L$ Y; k9 p
* [& j' c2 Z! z! U
: e, r- G% L3 _" ^
函数名: spawnl & [6 u+ K$ o: G- Z: U
功能: 创建并运行子程序
/ U4 O- i7 c$ ]用法: int spawnl(int mode, char *pathname, char *arg0, 3 N8 B R# j; V
arg1, ... argn, NULL);
* ?! `0 C. o' @- C; M- D- O程序例: 
, e- s! M0 q9 ^- Y$ D#include <PROCESS.H>: [: G6 r; n- N" G% P
#include <STDIO.H>
6 ~1 Z6 s; ?- v# q* x#include <CONIO.H>6 `6 Z! w) p( z) Z
int main(void)
) {/ d7 L2 s8 v8 S{
5 l0 G; [" n4 }( X* pint result; 0 n- E7 E, H/ c- O# G8 g
clrscr();
" d1 W2 W- R, k' Z/ H& cresult = spawnl(P_WAIT, "tcc.exe", NULL);
% x) s/ {4 _) v/ @: I5 H7 s \if (result == -1) . ~# q9 H$ O ]; T) A# t8 N& `- n: H
{
 c, |% g8 y7 _9 y9 l9 ?# D& v, W% zperror("Error from spawnl"); ; P$ P# H; I0 E0 _4 ]# K; V4 D$ l
exit(1); % S2 i' q6 r( Y c- Y) o
} # @4 x: M# |! ?* u
return 0;
$ v0 p: z' T4 }3 d4 c} 3 l8 m$ B F9 W9 h d
0 o3 O/ E/ Z* q& k" ^! z* X

2 b! `/ u% d* I4 u0 W+ c' D函数名: spawnle 8 l) j) P h, l0 ?4 @
功能: 创建并运行子程序 8 U& m3 [2 v0 n# m% T0 {) V; m$ Q
用法: int spawnle(int mode, char *pathname, char *arg0, 8 E5 u8 v( ^: x# f* k) K$ |
arg1,..., argn, NULL);
" {' t+ ^4 Y, g s: P) D程序例: 
4 D! B- D. f( \* e m9 L/* spawnle() example */ 0 A. P' m o9 i& v! X6 o& B
#include <PROCESS.H>1 ~* h' a- X# c; i
#include <STDIO.H>% A, Z# W! x- l" M" U
#include <CONIO.H>
, L, ^! o# p+ N0 Y6 Jint main(void)
) I8 y3 x8 S( L2 W: l1 ~{ & M) @7 C6 g; g: h$ Q
int result; 
! ]- a* a K8 m. c. ?clrscr(); 6 G: r2 E) e, a0 J" M
result = spawnle(P_WAIT, "tcc.exe", NULL, NULL);
: e k) w9 R/ L9 X" |7 q" vif (result == -1) 1 f1 T# s6 |5 J# V5 [5 {" s) C% k
{ . K2 m i% P. L
perror("Error from spawnle"); : Q3 H5 ^3 l v, K; O
exit(1); % z3 b% G3 e/ L2 f9 s2 d1 @
}
4 [ P, u* E& t, jreturn 0; . |! R4 }" {3 F7 C) J) @: c; u
}
. p0 Q. i8 {7 \6 Z* K6 b, |9 C. W% p( R

& K4 [ O, q/ x' s3 B m( _+ q4 W! R) ~6 Q; t3 ?4 U
函数名: sprintf / f* }' J) p/ e0 ^ }
功能: 送格式化输出到字符串中
0 V$ \& C+ N- }9 [) J" N+ Y* }$ J用法: int sprintf(char *string, char *farmat [,argument,...]); . e& k9 ^( ]0 G) U g/ I
程序例: 0 v( }5 q# P' h
#include <STDIO.H>$ O r0 q; w2 k
#include <MATH.H>
& q& q( F3 n2 b! X; `% Pint main(void)
* B! `+ t2 u9 m }- y0 i; r$ c{
" C1 o2 H& j4 x/ _# G/ z9 t+ \char buffer[80]; ( P7 X1 t5 Z# Z. O8 P# C4 U
sprintf(buffer, "An approximation of Pi is %f\n", M_PI); v7 C) `3 t* @; e
puts(buffer); " X; a$ _' h* v% W# ` W0 A7 [
return 0;
. a. s' p" c: `$ A# M: \} , U! f7 T8 q9 }4 _( o* s2 f- z' \
9 t/ I! k0 E }# T

; M) z3 D2 o3 l' N函数名: sqrt 
* O# e4 }8 ~2 y( {; D. _( e功能: 计算平方根 1 H! K! Q1 l, A" Q* \. i1 \( m2 f
用法: double sqrt(double x); * K) t6 u1 Q2 n5 e; r
程序例: 5 D- _& D3 Y2 \+ l$ @+ c( A
#include <MATH.H>& ^" l+ a. g, a" b
#include <STDIO.H> V* ]: x/ Q# ]9 s8 l& a
int main(void) . k3 w! J% Y. P! u% J
{ $ p5 n- a1 R" p$ a+ R9 @
double x = 4.0, result; 
% ?4 v; Z/ h" _3 z0 cresult = sqrt(x); ) N" Z: }: h% G7 t% {, Z: G
printf("The square root of %lf is %lf\n", x, result);
+ L5 W& e1 j7 e# H: S. yreturn 0; & |* H8 B- v0 b, Q9 d5 v0 O
} 3 m* A. ~/ M' W8 F

) b+ o; B' t' L: d8 l/ p函数名: srand 
- U( f- \' n& E- o3 r功能: 初始化随机数发生器
; q$ f$ H" O( Z' @! @用法: void srand(unsigned seed);
; u( P# l) u, i& C程序例: 
- C" y. p" l1 v" L( o#include <STDLIB.H>
9 R y7 Y3 A$ o6 c' o' p4 V# ?#include <STDIO.H>8 s1 A- b; p5 Y- f9 N
#include <TIME.H>) J' k7 h* T# W8 q1 w, X8 v
int main(void)
2 \% Q+ {9 z$ |; ?( T+ K0 Y{
' L1 A1 z% E% {* y+ @5 uint i; ( R; w5 ~$ \0 R s& Z
time_t t; 3 o3 \- C1 s( g# b
srand((unsigned) time(&t));
, _$ M1 x: C0 `! z g( p1 Jprintf("Ten random numbers from 0 to 99\n\n");
1 ~0 r3 b1 j( h l+ L2 L! L6 Nfor(i=0; i<10; i++)
: R* S2 }) n. Y" O- o3 ~8 x- l' Aprintf("%d\n", rand() % 100);
1 y0 `4 [6 Z6 Z, {2 Y, ~$ v& oreturn 0;
' m; G7 b0 ~+ u/ ~3 `5 \} ( A; p8 a6 f3 C9 C/ Z4 }. d+ p

& z' p" x/ m2 n: w/ `
- }. F) v8 t( j, i+ U n4 r函数名: sscanf $ P4 U. x4 Y% H1 u9 e- `
功能: 执行从字符串中的格式化输入 ) @; Z7 z* V" x+ j( i) M
用法: int sscanf(char *string, char *format[,argument,...]); ! Z) W8 r5 l: y
程序例: 
6 t+ y9 L! {- |! q8 V: B#include <STDIO.H>
% S1 u& ^8 q! r7 |#include <CONIO.H>9 _7 T+ C+ \; a/ d
int main(void) 0 s1 P% P# c9 G
{ ; ]$ t! K& [/ ?# Q6 T. p
char label[20];
# ^8 v- z9 T# ?1 R) W- v% dchar name[20]; 9 B3 G7 S+ X' _% P6 @+ r; [
int entries = 0; ' `) t- N3 M+ p2 X( e0 z, j7 ~8 H
int loop, age; 2 i( ~1 R4 x. n. k# ] W2 W0 d* g. M
double salary; 6 |7 ^2 \# ~( H9 H t2 l: n
struct Entry_struct
/ i. Q" k( O `% y{ + O1 y; R4 w" u( G) L# ~$ }
char name[20]; * j% M) n" F0 @: o' K. N* l
int age; 3 G1 d5 [8 S( Z. D" g b
float salary;
( m# R; M! n N' L. s} entry[20]; # ]; J9 T4 i, H+ {
/* Input a label as a string of characters restricting to 20 characters */ ) K @! b/ @. P& o; ^+ [0 H! b
printf("\n\nPlease enter a label for the chart: ");
" F0 U+ m" q5 Wscanf("%20s", label);
- A# k `+ b9 D+ ^& ~# e$ {fflush(stdin); /* flush the input stream in case of bad input */ ' x$ y6 W8 X: \& Z E" A7 o
/* Input number of entries as an integer */
, M2 K- v" r3 w' L, x/ ?printf("How many entries will there be? (less than 20) "); / b( s, i3 J( R' K/ V% S
scanf("%d", &entries);
. }$ |: O7 z9 l. J& Yfflush(stdin); /* flush the input stream in case of bad input */ 
' Y e8 H& T2 T( v! ^8 F/* input a name restricting input to only letters upper or lower case */
+ V, [9 _# @$ u, @2 M; Ofor (loop=0;loop<ENTRIES;++LOOP)
! U& ?2 [8 t- a { + v9 t- @& M) h' r4 P* e
printf("Entry %d\n", loop); ) M) A8 a1 [, d, f8 i4 \% R
printf(" Name : "); + y$ L$ k7 f; T
scanf("%[A-Za-z]", entry[loop].name); 4 J. |! @" I; v: [. ~' P
fflush(stdin); /* flush the input stream in case of bad input */ # {! s0 S" G5 \" @
/* input an age as an integer */ V( m8 A) A! V' k
printf(" Age : "); $ a+ k1 D% e/ J
scanf("%d", &entry[loop].age); 7 X7 l1 g% G8 l
fflush(stdin); /* flush the input stream in case of bad input */ , b: k+ n5 C0 a1 N% K* Y0 i' y
/* input a salary as a float */ 1 D7 w s! d @- E
printf(" Salary : "); + R7 @$ p) s: \/ H
scanf("%f", &entry[loop].salary);
6 [) _- \, F3 A4 n# Efflush(stdin); /* flush the input stream in case of bad input */ 3 ~* U' k0 Z: n4 e0 }
} / S) }4 H& W! d% h* T9 J2 t
/* Input a name, age and salary as a string, integer, and double */
' H4 u$ `$ Y( _- H, w0 uprintf("\nPlease enter your name, age and salary\n");
- C8 ^1 T f2 S- tscanf("%20s %d %lf", name, &age, &salary);
/ W, w, | b$ Q& v- X
( k" N- S6 [* ~" s. C9 d/* Print out the data that was input */ 5 B* e3 ~ w: L0 V) l0 @
printf("\n\nTable %s\n",label);
8 i/ C) Q4 v- E3 O0 U9 g2 P1 N. q# `printf("Compiled by %s age %d $%15.2lf\n", name, age, salary); # Q, Q/ d6 _, b6 |0 ]: D' N. {
printf("-----------------------------------------------------\n");
* u4 Z- J& }$ w# F+ n+ gfor (loop=0;loop<ENTRIES;++LOOP) + B/ _" z6 ~. ~: B: A% a; N' U7 o6 m
printf("%4d | %-20s | %5d | %15.2lf\n",
3 f: X, _5 U4 Eloop + 1, - V0 I3 V" W6 M7 m1 p& E& l
entry[loop].name, 1 w# A) N% j+ s! B; T/ R3 F3 L$ d
entry[loop].age,
% u: q4 ~$ q* d) eentry[loop].salary); ; r, E" Z3 a9 @9 o+ R
printf("-----------------------------------------------------\n");
0 k4 P& a2 `& P( x( @0 x" u0 Dreturn 0; / K# \5 g6 y; F. j
}
, x2 ~: t7 r9 {! I) A( u' u8 f) j5 t

+ W6 Y1 L" m i) A- r函数名: stat & l5 P4 K0 l6 |( \% Q
功能: 读取打开文件信息 / M3 |: g6 [8 q+ x$ s
用法: int stat(char *pathname, struct stat *buff); ' f/ E; X3 \: V; z4 K, F. Y( H; u z
程序例: 8 o {# g1 S3 a% w1 m
#include <SYS\STAT.H>
' q* Y, T0 D) S6 [. z#include <STDIO.H>, ]7 \# v( y" M' Y3 @- T
#include <TIME.H>, Z3 J+ j- X9 s" h2 T
#define FILENAME "TEST.$$$" & P3 K; W; d Z
int main(void) 7 Q: I8 ?; R2 l+ h+ E
{
0 g% M$ r3 m( a+ }struct stat statbuf;
* ^1 s" |5 @! r& r& s5 xFILE *stream; 
/ D( k! T: s2 N6 J/* open a file for update */
! l( `+ ]8 s1 o& k) h' M# Rif ((stream = fopen(FILENAME, "w+")) == NULL)
$ N# h! B9 o+ n, I9 G{ 6 V# k5 }+ x+ N
fprintf(stderr, "Cannot open output file.\n"); ) r5 w- V$ x+ N: _" _2 g% f
return(1);
; w; q4 V$ j+ ^( p' b: s* h} ( m1 `8 H8 E* b- [) W
/* get information about the file */
5 Z7 ^0 a" b# j* j" Ostat(FILENAME, &statbuf); 1 v1 ?% K8 B( w
fclose(stream); 
' f8 A& V& x! D/ ~9 v4 g2 _/* display the information returned */
* d5 P g# L8 u( \6 |$ B8 Qif (statbuf.st_mode & S_IFCHR)
$ X: ?0 s3 _# ?. P% j- T- dprintf("Handle refers to a device.\n"); 0 I4 t) B7 }8 `: u7 B9 P2 Q0 h
if (statbuf.st_mode & S_IFREG) 1 }0 N+ s) \" C0 ^5 G
printf("Handle refers to an ordinary file.\n");
" g3 @8 ]7 i. {& P- l0 V4 Rif (statbuf.st_mode & S_IREAD)
/ q, J* v! p+ iprintf("User has read permission on file.\n");
5 V3 k. ^% i3 h, v' b) m4 y9 j, Sif (statbuf.st_mode & S_IWRITE) 9 ]0 p2 Q% A6 h2 w# t, U) ]
printf("User has write permission on file.\n"); 
- P8 y3 b3 j, ?; ~8 Q. i) y+ Fprintf("Drive letter of file: %c\n", 'A'+statbuf.st_dev); ; z8 `7 R9 X; B& _: c9 i6 N
printf("Size of file in bytes: %ld\n", statbuf.st_size); + A4 W/ ?# \# r3 H$ S6 B+ c
printf("Time file last opened: %s\n", ctime(&statbuf.st_ctime)); / Y2 t# A/ [$ O. E
return 0;
* i. y8 S# [* y6 o3 Z. H+ {}
6 T/ X. P+ q) P
; N0 {2 E9 [( M" r1 L" p* s: i4 J
! |" @- t2 ^9 g6 m+ t6 X
4 Y0 k1 ]4 g! O* Y函数名: _status87 . G! G/ A9 Z: c% K0 Q! O
功能: 取浮点状态
6 |3 G: {0 j" t t! H0 u6 K用法: unsigned int _status87(void); " ]# A5 E' i! Y" k2 y5 |9 k
程序例: # n0 ~+ i# A, d6 G& r
#include <STDIO.H># d1 N9 @4 I r5 A
#include <FLOAT.H>) a+ S& q. L4 B9 K- ?- c) E
int main(void)
* M6 G+ r1 z$ n+ J* K{
3 W- N. C C0 @" e+ [float x;
; O& ^3 g+ Z& v. Udouble y = 1.5e-100; 
3 ]- I& }" s* Y/ K6 ?printf("Status 87 before error: %x\n", _status87()); 
/ @) ^1 u. q- w8 [+ ^3 gx = y; /* <-- force an error to occur */
, E2 h& N- e# x8 M# jy = x; 
- k1 n# Y. |+ [0 qprintf("Status 87 after error : %x\n", _status87());
$ H! F/ p U6 `3 p; d% f3 r0 lreturn 0; 7 i! a5 r: C( B+ E7 N- n
}
" K- ?/ Y* K. y$ E% J! J! h8 k& ~3 ?$ a# f& H5 Z D- T5 R

8 ~" ^9 Q- @7 D! @. ~函数名: stime 
3 |5 l# ~8 r8 d/ z8 U) C, I1 F功能: 设置时间
7 s5 z }& G, \用法: int stime(long *tp); * Y3 U) J, M" h% Q. Z! T, L, x7 D
程序例: 
7 |5 e. D6 Y- M* c) u' Z#include <STDIO.H>8 s/ y% b9 [/ O( `
#include <TIME.H>
3 O) r! A- Z: j6 g7 A#include <DOS.H>
- |8 b( L: j9 B- ]5 K1 L/ sint main(void)
( u7 ~" e. N3 }, n6 T{
- w1 b+ {" e. z( htime_t t; 6 d5 P- s, ]7 ^3 y
struct tm *area; 
) _. R( T/ P* E; t2 w. kt = time(NULL);
# `- p6 ?8 s# H' l# a/ M3 larea = localtime(&t);
4 y& C5 O X! \1 `# }- Zprintf("Number of seconds since 1/1/1970 is: %ld\n", t);
/ h! g6 o: K$ a& X- gprintf("Local time is: %s", asctime(area)); ) j3 x9 x! W2 h& f" T1 `0 k I5 Y8 O
t++;
( V# I- I. `6 K3 A) p) K: sarea = localtime(&t);
: r5 X2 A6 `- a% U, N8 }printf("Add a second: %s", asctime(area)); 
! [& w# y% d8 P' }0 A, |# \t += 60; + Z5 O. ]( J3 W
area = localtime(&t); ( p+ M3 x: N+ c" h' B8 J% j
printf("Add a minute: %s", asctime(area)); 
6 ~/ r; [9 i4 @0 b% w9 a$ |t += 3600; . a7 k( ]& d1 _% }0 |7 m
area = localtime(&t);
% u, N# f- D7 x/ T; c9 @( P4 |' Iprintf("Add an hour: %s", asctime(area)); / ~8 |% X }+ X% J! S& b7 e
t += 86400L; ) D: _: F9 K& c
area = localtime(&t);
/ f. [- L6 p$ B& [# uprintf("Add a day: %s", asctime(area)); ( x1 P; m$ U7 u. x- [- \
t += 2592000L; / l) P1 B9 l8 g# H1 C
area = localtime(&t); 6 M2 V D) ]2 [( ?. I. G# T
printf("Add a month: %s", asctime(area)); 2 j6 I$ n/ o4 \( [1 {# C" z
t += 31536000L; : N( j4 ~; {+ g. n
area = localtime(&t);
" a) ^, I, X. N. mprintf("Add a year: %s", asctime(area)); 8 ?' o3 H: c' Q0 @$ ]& \2 `* y
return 0;
2 W; Z& T" @; P4 v i3 {} 
, i( O' I; x6 Q5 z4 t
5 S" V& Y, ?) j7 E+ m- n5 e% |8 b& E, U0 ~

1 h) i! U$ H: v* f函数名: stpcpy & |; C. e2 `3 H- {$ I; y
功能: 拷贝一个字符串到另一个
, W1 a" A8 c' T2 h用法: char *stpcpy(char *destin, char *source); : Y6 M2 N+ n: p3 K& c B+ S9 o6 `
程序例: 
+ N- W# Z+ ~6 c; K# {; y#include <STDIO.H>+ Y6 x" S9 t% U+ |
#include <STRING.H>
+ W" T% O, T* |7 v8 U3 aint main(void) 0 f8 x& T- V+ U1 @& O
{
) d% [- Y* P$ S* Hchar string[10];
$ F, ~ v( ?$ K2 ^8 ychar *str1 = "abcdefghi"; 
3 [' ^6 D9 ?! t$ }2 K2 B) Lstpcpy(string, str1); / _0 I3 H. j6 @$ T
printf("%s\n", string);
7 @& y& I; ]* k/ `' t7 Z* Greturn 0; - I5 Y) J; A+ _! m
} / K% P; r' {3 V7 M/ @7 R

" n1 m0 A( U; n9 t/ C% \
2 b, e2 l( u2 D. r
( z7 [* t4 J e2 f$ \3 v函数名: strcat 
4 |) }* ~ @ ]6 m( K/ ]) E! M功能: 字符串拼接函数 1 c! A2 N! m) d4 |) f, J) t+ A
用法: char *strcat(char *destin, char *source); ; O' S% M+ q% F' {
程序例: 
/ l! e U5 n2 }4 ?8 K& ?3 p#include <STRING.H>
9 t; X8 J4 S, [+ I#include <STDIO.H>
+ ]; ]+ P. j2 |/ ^int main(void)
8 L% F) @8 f% T5 k& o' ~. t2 X7 S{
" ], j- ?$ @' a" L1 vchar destination[25]; & ] r" {* a7 a) Q
char *blank = " ", *c = "C++", *Borland = "Borland"; 
: H* R8 ]- X+ ^0 dstrcpy(destination, Borland);
' B7 n6 d! y) @" A* P) w! A. G. `strcat(destination, blank);
& J" D7 ~$ U; }, Z8 o1 [strcat(destination, c); 
- ^* ]8 @( Y+ i# N6 b1 A2 l3 j2 Z' M7 tprintf("%s\n", destination);
, `8 Q% I* L8 n( hreturn 0;
0 c$ v) t: p" D3 E6 C! ]5 }} 2 j; r+ A# f3 G- k& p" T) c
$ k! Y4 g s* m$ j) t1 O+ @

8 J( e5 }0 k8 j1 D) C9 c! G
 s% J0 a7 }+ v) Z4 `7 u6 Z函数名: strchr 
% y! ?$ l# j' e0 b, ~; y7 [2 l功能: 在一个串中查找给定字符的第一个匹配之处\ . ?6 q% } p/ t# |4 \4 m7 R
用法: char *strchr(char *str, char c);
" F( e8 E5 a) ]$ i1 g% T7 p程序例: 
/ [0 a7 j' J3 O* a2 l+ d#include <STRING.H>
# k& R1 X; o3 }1 F#include <STDIO.H>
# n0 z9 e K# r1 kint main(void)
! I# T8 ?) p0 b, {2 J. v: r- y{
5 g6 {" P+ ?" ~char string[15];
0 c. F/ W& L% o- H4 Z2 {char *ptr, c = 'r'; 1 Y- `0 j. H: h+ @; }9 i& U
strcpy(string, "This is a string"); 0 k& b: g; k6 W4 H! B
ptr = strchr(string, c); ) Y( N+ w$ h- a# z
if (ptr) $ Z. O9 ?. F4 H- t
printf("The character %c is at position: %d\n", c, ptr-string); ! | U! t9 Z% Q5 e. S [
else
& M% O d; M' l% M: a5 ]2 Vprintf("The character was not found\n");
9 A! O' h. ~/ Q8 ~# i9 s) }return 0; ! ~2 I4 H/ ^- X3 D+ h
}
: ?7 i$ C0 G0 U; a/ v' n; _, A
; s1 x6 ~# [2 Y7 F/ G$ h- b# e
, P) n$ Y; G( ~
6 }; J, H- ]$ r0 {函数名: strcmp ; Q( Y. t7 Z. l! m1 A9 a
功能: 串比较 : H8 c/ o6 v; y4 j) l% j/ q
用法: int strcmp(char *str1, char *str2); ; D+ L8 S2 w( A% O
程序例: 2 ?% ^ V# I0 H2 F) k/ ~
#include <STRING.H>
" e* R* }! i1 q- s#include <STDIO.H>/ j( _, S( V* v' [
int main(void)
1 r( u' q! R/ U" @* \{
: q% I5 Y8 k. d+ ^6 H. Ychar *buf1 = "aaa", *buf2 = "bbb", *buf3 = "ccc";
9 x1 @+ a( F+ F0 hint ptr; 
! W% a; H4 b+ Dptr = strcmp(buf2, buf1);
 w- a' N. w* vif (ptr > 0)
! E, L! A! R! G5 C. Bprintf("buffer 2 is greater than buffer 1\n");
. e N3 k0 n9 _' J8 C3 yelse
% S. d: w+ ?! |* w/ bprintf("buffer 2 is less than buffer 1\n"); / `6 C3 U5 b, R' `! R+ d
ptr = strcmp(buf2, buf3); ' H, S; n3 B0 A6 u- A; B
if (ptr > 0)
0 O% \0 W' A+ F. p) Hprintf("buffer 2 is greater than buffer 3\n"); ) w+ n( l2 T5 Z, u4 l
else - v; S; X* Q- N1 |, ~7 _
printf("buffer 2 is less than buffer 3\n"); 
& {& J" _+ H2 q7 m2 d! i9 D2 Freturn 0;
, ]- r4 G# f) F$ D}
 g& x9 g$ E! a: l2 O1 {2 _- j; h3 z5 _% Y, v

3 ~ M* l! H! I
, `0 c) ^4 l9 j1 L$ p) R函数名: strncmpi 
2 f* ~( H# K4 R1 g功能: 将一个串中的一部分与另一个串比较, 不管大小写 6 j, n$ w$ y7 G$ B# }% N. |" W; K
用法: int strncmpi(char *str1, char *str2, unsigned maxlen); & o) \- x- e6 z0 d1 b7 s
程序例: 7 M" _ ?. L( S, X4 ^) Q. v" G
#include <STRING.H>
- E o4 s- Z# Q9 k( k#include <STDIO.H>
) l3 q8 H$ F$ T k) @( b7 B ]- Wint main(void)
% ]- `( O! ^0 O% Z3 s6 Z{ " l$ j1 |. Z( p) V5 c: }- B+ d% I
char *buf1 = "BBB", *buf2 = "bbb";
* R, J* r' P9 G" P8 H" I* }int ptr; 
% z6 B/ s( f q$ B& _2 K% P5 Optr = strcmpi(buf2, buf1); 
. q9 W. `5 h0 ]if (ptr > 0)
$ M3 N# r+ ]! Y" R! ?4 h+ ~3 eprintf("buffer 2 is greater than buffer 1\n"); " V+ V9 G# q3 f
if (ptr < 0)
) a: `; D' a) g: {9 k3 aprintf("buffer 2 is less than buffer 1\n"); 0 \# g; W) P3 K- Z2 x
if (ptr == 0)
0 n( ]. Q3 g/ W: j- c1 j* pprintf("buffer 2 equals buffer 1\n"); ]7 S6 E- o- E! e) |
return 0; $ b1 O3 o) Q$ }; R
}
; B# `, h' }" D, e
2 s' M1 R( B" i" u6 E8 \: ~7 q
% L& N0 b5 L2 h* |' }' g+ ]/ X! a7 u
函数名: strcpy 
' \( d# f5 o7 `* o功能: 串拷贝
9 Y& X( Q7 ]) v% m/ ^6 j$ g2 l用法: char *strcpy(char *str1, char *str2); " g( T+ u& R+ z' _
程序例: - U" D! |( \3 b% U0 b! m
#include <STDIO.H>
% }9 A# y9 [; v9 `1 u" t; B7 I#include <STRING.H>; R" E) A4 h( [4 w0 `
int main(void) . B6 s- C# W. z, j
{ ; y! L6 i z6 {
char string[10];
$ I I+ { } K' q8 Mchar *str1 = "abcdefghi"; 
8 q* Y* {4 ^$ p$ A; i/ \strcpy(string, str1);
# v. d% O9 Q2 Q, g' Mprintf("%s\n", string); ! V; R; b% D2 B
return 0;
! }: t% k1 [9 a& Z3 r5 _}
& x) ^5 k' L2 E7 Z: i# M' k7 b3 o. h

8 y# G r; B! h& C, y
8 n# Q2 I, u6 t0 G函数名: strcspn 
, ^2 J$ _' Z1 {- u9 p d功能: 在串中查找第一个给定字符集内容的段 / ?8 M6 a9 ] j
用法: int strcspn(char *str1, char *str2);
7 g1 X$ @0 p4 P3 y+ Y4 }9 R程序例: U3 F$ R% @$ ] o3 A
#include <STDIO.H>6 r7 o$ V- w2 u- M1 x' j
#include <STRING.H>7 a% g$ [ x3 h, ^8 r/ m7 }
#include <ALLOC.H># i% w) G/ o% M9 j* X, }
int main(void)
( \" m/ `7 B- u8 r% J i U{ - W. Q: X I! Q) p9 ^" K
char *string1 = "1234567890";
3 b5 o, M, ~9 T+ C3 f! Vchar *string2 = "747DC8";
6 R: Y; j8 a: V8 ~1 }int length; 
2 |" t* ?9 b4 Y4 }; T, Qlength = strcspn(string1, string2); 8 m4 x7 ~, O0 _+ X1 W5 k8 ^
printf("Character where strings intersect is at position %d\n", length); 
3 \7 w/ [/ X y, ^- o+ {9 wreturn 0;
6 e& r1 [ Y. ^% h} - H$ t, \7 X% X9 g0 I' ~2 p

7 ~8 c# O. Q* \; ^1 q; R% e
3 d. m) [" g) V+ a5 D+ ]. P# M( W7 l' j/ }" x9 O$ T
函数名: strdup 
% I! W- Z# _. h& _功能: 将串拷贝到新建的位置处
1 z- d* @0 c* G6 @+ @( B8 H用法: char *strdup(char *str);
, L6 X! g& M! s. j) R, y4 _程序例: 
" O" G# G0 g; B, j% _#include <STDIO.H>
8 P/ i7 X' A( E" q1 `#include <STRING.H>- \% i( Q; A- \. ~" p! @+ p4 R
#include <ALLOC.H>" \4 Y# c. k+ H0 O7 o/ m
int main(void)
! I2 M: a- J( c8 h6 G: V: Z{ / n5 f9 h% o7 i: N/ i
char *dup_str, *string = "abcde"; . A- s4 T& \4 F$ M8 B2 e
dup_str = strdup(string); 1 F6 E% x. s+ g: a( r; ~4 I% e
printf("%s\n", dup_str);
( q0 O+ ~4 i R) S+ `! b" Ifree(dup_str); 7 x/ N4 y4 x$ r- C8 q- q7 V+ P6 i
return 0; 4 `# B2 u5 N" b2 Y3 ?: F* j; F
}
" m0 M+ ]7 i' n; T5 }7 s" _/ H. ^( t% f) v1 M

5 s$ c' w1 R; C( x, d$ T* R. _: Y! z# \9 n5 d
函数名: stricmp 3 ]) Y$ U& j W: O) v
功能: 以大小写不敏感方式比较两个串 , J0 O5 K9 l' `$ _
用法: int stricmp(char *str1, char *str2); ' b" |' Y( N/ f+ |0 j
程序例: v$ [3 v' G* V$ d0 [( j" M# x! f
#include <STRING.H>
/ \* t; o( B2 D/ M* \: X! \' P#include <STDIO.H>- R9 a1 M* q6 X) h& N
int main(void)
4 t0 \# U: t3 E; A& E7 g{ # B- n- s% N* v; a
char *buf1 = "BBB", *buf2 = "bbb";
2 b5 y5 ]: ^: x P$ Wint ptr; ?# d4 F) W( U
ptr = stricmp(buf2, buf1); 7 p7 ^4 K4 C4 y! W8 q3 [6 e# O
if (ptr > 0)
printf("buffer 2 is greater than buffer 1\n"); ( M, T) K6 H" y6 i6 V, H F+ Y( z
if (ptr < 0) 1 G: n4 {5 ~+ `5 s3 D& |/ d
printf("buffer 2 is less than buffer 1\n"); ; u( v3 _4 _' T8 P
if (ptr == 0)
/ v# n5 g# d8 u8 K, e8 e! _ Vprintf("buffer 2 equals buffer 1\n"); 
+ s0 V+ \& O: M1 {8 x% Zreturn 0;
) w/ ^. A4 u; |* P( _) c1 T) F} / r7 o4 p" O4 g1 N0 t

3 D6 t3 |- a. L% u0 x- p
4 Z$ v% _' Q; @( Z( H- l函数名: strerror 
! g5 @, E* w% `功能: 返回指向错误信息字符串的指针
 z9 T9 g- p6 @( Q: p用法: char *strerror(int errnum); ) y: y# E& l% ?$ r6 I* T
程序例: : U3 N/ g. p m: |) D# \- C. Y
#include <STDIO.H>
$ t3 U& V6 i% }4 _#include <ERRNO.H>
; O1 L% K5 C, ]7 J% B P Dint main(void) + r2 E2 P! c1 a: [1 I; c
{
# g5 o+ Y9 B3 d- x! Y1 z& t0 G& Wchar *buffer;
% s9 e# z A2 ^2 p$ D+ v; tbuffer = strerror(errno); : y% Z X3 y3 F. e
printf("Error: %s\n", buffer); " U6 r$ K6 `( ^6 K% z
return 0;
/ J6 g t2 W% E) o}
9 E; \8 U! U E! U( Y# p$ H
: x( E' m; l: s, l6 W3 m2 {
9 f- x/ M" c8 Q4 D+ ~3 ?; f" ]
/ C N) v0 K- p, h$ g/ v+ x函数名: strcmpi # C0 e9 V( g r, q. ~' F% L0 [
功能: 将一个串与另一个比较, 不管大小写
1 J W/ _* G( |- s用法: int strcmpi(char *str1, char *str2); / T$ V. @% V: g! E5 p
程序例: 
, o+ u* ^' o7 t; B#include <STRING.H>
" a/ f: U5 _, t#include <STDIO.H>' L" ~3 \0 R$ W! v1 {- \4 y5 M
int main(void)
) z' l4 c, p* J* r0 ^0 Y8 Z{ m0 F! _* M3 w1 k9 N3 Z
char *buf1 = "BBB", *buf2 = "bbb";
) Y, y# ]( Y8 ^, @+ K! ^* y, |$ Dint ptr; 
0 x! Q. L# k. Q5 Q" d! Tptr = strcmpi(buf2, buf1); 
/ C- Y' [8 ~: P* Z! Zif (ptr > 0)
% T0 W+ L) s/ S+ N/ @4 y% J* sprintf("buffer 2 is greater than buffer 1\n"); ' w \2 U, A; a$ E B
if (ptr < 0) $ r! D$ \( r0 P" t; D) a
printf("buffer 2 is less than buffer 1\n"); " c y) g" E( v2 [' W' H! ?% H
if (ptr == 0) ) H% v* s" x6 V, ?9 C8 `
printf("buffer 2 equals buffer 1\n"); 
# _2 V q4 k+ ?- Z( q5 Creturn 0; * ^, h) P& X8 R+ s' N2 `
}
% m2 Z' r4 u0 h/ [
# u7 b% @: e" A: q* [6 Y, |9 n* w' o! m
% H) [0 x: }2 S ?$ s) X6 N
函数名: strncmp 
1 r; y F0 h! r1 m/ E功能: 串比较
: H% R X9 |: K( `# h) P/ V1 p用法: int strncmp(char *str1, char *str2, int maxlen); / S f+ P# G2 g! z
程序例: ! W' D7 {8 `. W$ E8 w
#include <STRING.H>) k$ x) l/ {2 L2 q* ?
#include <STDIO.H>
5 n% B1 g5 e8 c6 x! y! d4 ?int main(void) 
6 j% ^* Y8 g# S) t% ]: e2 Z) ]( i1 w{ ( W5 |0 j/ p" r
char *buf1 = "aaabbb", *buf2 = "bbbccc", *buf3 = "ccc";
8 j: e. B; K/ u' R5 a9 O5 R$ Z& bint ptr; , Y l9 ^) M- I
ptr = strncmp(buf2,buf1,3); 4 g( K- Y7 @5 g# E
if (ptr > 0) - o+ o8 j j4 s/ P6 J7 ]
printf("buffer 2 is greater than buffer 1\n"); ) L5 {# a3 u" k' O- y" a. u
else 4 Y5 c$ k6 g( d1 V( [6 Z& f5 t
printf("buffer 2 is less than buffer 1\n"); 
4 b$ K- e4 d, T D' V* ^, T3 b. D# tptr = strncmp(buf2,buf3,3);
! ~# v( A5 m( C5 J4 aif (ptr > 0)
. W; [) u/ a9 G2 I) Hprintf("buffer 2 is greater than buffer 3\n"); 8 R2 ?) R* Z3 @5 k& p9 j& K. E) W
else * `5 }& C1 K+ f/ a
printf("buffer 2 is less than buffer 3\n"); # {" m" }( k& g$ D6 C2 A, g
return(0);
 d4 d+ [ C0 T# R}
- m7 t% l! l. g/ B+ m, E j# K5 q, }% y5 G6 {
7 r8 d2 s) ?+ b, m) N
函数名: strncmpi 
8 R: W5 N/ P& E功能: 把串中的一部分与另一串中的一部分比较, 不管大小写 ; O) C% o4 T& T( |5 @" `
用法: int strncmpi(char *str1, char *str2);
) w2 K u2 U' h程序例: + I+ m W) A5 X6 }7 \/ k3 p j, [
#include <STRING.H>3 X! Z6 [3 J- X8 E0 C; v' }" k
#include <STDIO.H>
& C. J* V7 f" v- ~int main(void)
. f. f* W* |! E0 T$ T% f{ 0 M$ o" t9 i) L- z' r* X
char *buf1 = "BBBccc", *buf2 = "bbbccc"; # c( f% M' B' J( E
int ptr; 
* K1 P8 h; s" ^$ a5 O8 `ptr = strncmpi(buf2,buf1,3); 
+ m! O6 P, ^2 ]3 }, v3 |if (ptr > 0)
, u: x) j3 l$ V& x+ t5 |6 kprintf("buffer 2 is greater than buffer 1\n"); 
; B' i$ }5 l( f" g- K6 S' d9 zif (ptr < 0) , _2 P Y, ~ K2 I
printf("buffer 2 is less than buffer 1\n"); 
1 \2 Z( y0 e) Z K# Q- fif (ptr == 0)
3 b% O+ ?8 k% z4 tprintf("buffer 2 equals buffer 1\n"); 
3 T7 Y( g* h6 ^. m# H" Xreturn 0; . ?7 [# {' \6 u
} $ M) z+ s$ _0 f4 p: }/ Q; I# W

; D4 ^8 V$ n; ~9 O, ~& q5 M
* o0 s6 O- U9 [; Y8 Q函数名: strncpy : _! n2 E1 Y% L! [5 b: q2 f
功能: 串拷贝 % h) U m: I3 K
用法: char *strncpy(char *destin, char *source, int maxlen);
$ Z" Y7 B% ?% Q& Z) Y: O5 t程序例: 1 X0 O l' Y( r" O1 |0 ]
#include <STDIO.H>" q# w+ t- x' l; C: V7 I$ Y7 Z
#include <STRING.H>
$ F; } }4 @. @1 |int main(void) & I% ]+ ~: `8 A: u9 ~5 y
{ - u8 O3 O- ]' {& M
char string[10]; 8 y( `: W0 Q4 k c4 A
char *str1 = "abcdefghi"; 8 W3 e! U1 g' o* k$ u( i
strncpy(string, str1, 3); " F$ f; S" G4 \% w$ X/ ]- } g+ y
string[3] = '\0';
" ~3 s3 o; e* Y. z& R( Yprintf("%s\n", string); : H+ h% k: s; q; g& D& o. v
return 0; 6 Q5 S- }% o% ?7 V. \0 x9 N' {& z4 C
} + {1 t, }7 M2 @+ d" A Z
$ T+ R8 P7 P: E' U( o" v% h; e8 I

7 l/ S; A% v/ h4 ]3 {函数名: strnicmp 1 Z. U7 T0 b7 k0 e' E
功能: 不注重大小写地比较两个串
0 e# J1 w) g7 W4 T+ b用法: int strnicmp(char *str1, char *str2, unsigned maxlen);
3 H: L$ E: J) V8 k8 e5 T% m程序例: # D( O& A* v! ^2 C0 `0 v
#include <STRING.H>
 u% l$ ~# v. x7 z! Z8 n: H#include <STDIO.H>
5 `( k! e0 _' Z9 Y# vint main(void) 5 I7 K5 Z2 |: Q. j! Z" R
{
 E" j; A) f: N* o5 gchar *buf1 = "BBBccc", *buf2 = "bbbccc";
8 a0 G- Z* O B+ F! M, Aint ptr; ( I o6 |6 Z. R* _
ptr = strnicmp(buf2, buf1, 3); 
; A& `- e' N0 l; |8 a C) Xif (ptr > 0) ( S9 X! y+ s0 P, m
printf("buffer 2 is greater than buffer 1\n"); 
' m8 l* x1 x$ H$ Q* y" vif (ptr < 0)
* L: [2 u: Y6 h* d6 Z; F) `( Cprintf("buffer 2 is less than buffer 1\n"); ' \4 o! u' k1 J2 x' t5 f) x
if (ptr == 0) ; b! Q# A' f( }: P/ E( P9 P
printf("buffer 2 equals buffer 1\n"); 
; d6 ?- H: {- wreturn 0; / v1 q% a8 W& L* ^+ e2 V/ h' g
} / Z4 F6 i' b8 A* n- y p) J
7 E0 e5 W; P) k5 l

- H) @6 ^) @; `% V/ W; M" e. [ \* V) l: C5 u3 i
函数名: strnset ) X+ X+ L) T, S
功能: 将一个串中的所有字符都设为指定字符
; d2 ]- Y, o" D: G9 n+ T9 l用法: char *strnset(char *str, char ch, unsigned n);
; r- n# Z' t# U4 Q- a) {% _: v# N程序例: 6 I( q) f0 C4 s l2 y
#include <STDIO.H>
+ \2 E2 Y4 H8 ]' c! a" L#include <STRING.H>
9 B- a( A( ]# F* o. `+ {int main(void) * c* ?3 T K# V% B
{ # ^, \* ^* O$ z* d8 s. h" a
char *string = "abcdefghijklmnopqrstuvwxyz";
2 @4 E* [ l: W$ ^% Achar letter = 'x'; " {9 U2 m: \' N% P! y& ^1 D
printf("string before strnset: %s\n", string);
' f8 Y) [& ^$ P- istrnset(string, letter, 13); ! U! [: ~3 b( n3 I2 b
printf("string after strnset: %s\n", string); . d) K! \& ?! z1 a4 I
return 0;
4 g9 q" |0 I9 F$ j x: n} 9 P2 Q/ [( [% |# B# _% r
: v* ?; ~8 u( v6 j9 Y3 }

" D' T* i) m! z4 Y: G' A函数名: strpbrk $ t' ?" j& A) L, O2 t4 ^8 p- h
功能: 在串中查找给定字符集中的字符
5 z' u2 {! t, ~5 N7 i用法: char *strpbrk(char *str1, char *str2);
% y6 c: s* B9 A4 Y% @. F1 T程序例: 
0 J* \) J/ |3 G1 ^' ?$ u#include <STDIO.H>
$ u) l4 w- } Q( h( [3 t; M, V& X#include <STRING.H>: Z( Y& S% T0 ^' O. } S6 o- ^ [
int main(void) i: ^8 `* t4 b5 h5 a. w
{ * m& T( c% R4 N' L% q1 j
char *string1 = "abcdefghijklmnopqrstuvwxyz"; 1 e9 @( D& J5 T( l" E6 u
char *string2 = "onm"; 5 Q2 C+ B3 d O
char *ptr; 7 Q( Q6 y O( C* d- D& q3 p& E2 ]
ptr = strpbrk(string1, string2); 
- _9 f& c x, k* {if (ptr) ' L9 h2 C7 l# u4 b# m3 O* p
printf("strpbrk found first character: %c\n", *ptr);
9 r2 {' u8 c; U, c, M6 q8 Melse $ q" e% I% b: s/ t: j
printf("strpbrk didn't find character in set\n"); + Q9 P' x2 z; S& k0 i; y
return 0; : `- D* M' J. Y
} - ~9 U& x1 Z: h5 ?2 y" @

6 Z$ C: T7 |4 R: o8 K: o% k o b, I8 H$ S/ D/ D3 ~) S

, L" w# B \4 q; u2 c% E0 }+ S, C函数名: strrchr . A( o: `4 P' V4 k
功能: 在串中查找指定字符的最后一个出现
2 Q# P% |( A+ r' E3 ]用法: char *strrchr(char *str, char c); 6 g8 {! s) l. k
程序例: 
8 H( W3 b* a1 W* U8 ]8 M% P3 J. v#include <STRING.H>
2 d7 I1 P- @- e f* w* ~' c% f#include <STDIO.H>0 G% B9 N8 Q. H* M& G7 s
int main(void)
6 z4 p/ l. p. b) {{
9 j9 q; N# K& b5 F U- x# N' `char string[15];
( f8 o6 L2 i8 ?/ v* ^# f" R+ Achar *ptr, c = 'r'; 3 j' M8 G, n* n8 e* G
strcpy(string, "This is a string");
& x) O% j3 k7 }2 F, Xptr = strrchr(string, c); 4 b) z3 @0 P, ~
if (ptr)
$ w P6 y8 X- [0 D5 o" ?7 Rprintf("The character %c is at position: %d\n", c, ptr-string); / T9 {1 V0 a# [1 A4 k; L. h/ H6 O6 v
else ( E8 X! m' ?7 Z* ~
printf("The character was not found\n"); ! c$ T4 L, s3 Z/ {# x3 a
return 0;
$ W: R" n% n- O- W2 r P} 
+ E1 U6 r) `, z0 y! _% n! z
8 L3 h6 _# H5 p' J4 t* j# M9 U+ b% |) A- ^# m# e
% z' M% c! e: l* q3 p1 R
函数名: strrev ) S; A, [+ G/ `$ V# ^1 u! k
功能: 串倒转
8 @8 s! l/ Y1 N3 L用法: char *strrev(char *str); " G% z+ l$ y) u+ X2 d8 C E
程序例: }' ~1 |* w, {
#include <STRING.H>! w7 \- b' V) K- s- V
#include <STDIO.H>
# P& O1 y W. ?( j- v8 B. [5 O* n4 vint main(void)
, c* L4 G1 V1 b0 F0 l3 K. S{
: i7 u* |% c8 _char *forward = "string"; 
, u, i p+ Z) ^5 Q+ t1 X1 Xprintf("Before strrev(): %s\n", forward);
5 p" [' x" k. p! j2 c$ F' Kstrrev(forward); ! T% h! h; t8 i+ Y. a+ ]) |
printf("After strrev(): %s\n", forward);
/ O1 L F) u1 n2 Z* {3 Z" dreturn 0; ) N: p# O' v, {* y. v$ ]" R
} s/ }5 B* N) y0 t

" {( q, [ u2 l2 Q7 J+ S0 ]% @函数名: strset 5 D, e. C+ E$ U; |; ~3 R4 R
功能: 将一个串中的所有字符都设为指定字符 8 R' P+ O1 _7 H! {, n8 K
用法: char *strset(char *str, char c);
0 ^: @( P2 P% Q1 C程序例: 
+ }* Z% j, L/ H) I. Z u& N#include <STDIO.H>6 _/ P8 x9 B" ^+ ]* p; k* i
#include <STRING.H>
# H! g) `* c: B, y- Wint main(void) 8 j6 Y. m4 K" U" B
{ # o; M2 F. L; ^0 F
char string[10] = "123456789"; e- n1 i1 R/ G
char symbol = 'c'; 
6 |6 T2 w2 F; a/ T% n: Uprintf("Before strset(): %s\n", string);
- j& Z3 {4 F! ~4 Nstrset(string, symbol); ( P0 q% B& y4 v/ S% `
printf("After strset(): %s\n", string);
2 m' A( T6 H" B0 m* l1 R3 ereturn 0; - e; V1 _/ X7 @' t" }( f7 I
} 6 ]7 c+ ?! m- e2 D: L

- X8 [2 ?; p" u! {" S# C1 W( Y# }; p) n) g) A

 @3 b- S- r- b" D+ d函数名: strspn 
; Q8 O u( J! K3 ~1 D. a功能: 在串中查找指定字符集的子集的第一次出现
" T+ b" Q5 l1 ^% |* `" B( @9 F% `用法: int strspn(char *str1, char *str2); ! k' ~) B$ M+ d' u0 }# o, m
程序例: / d: U4 _- d* P! i3 Q* a3 a9 v M
#include <STDIO.H>
7 ]1 g3 _: r/ B1 X& Y#include <STRING.H>. @5 ~3 {+ M5 y) ~0 d
#include <ALLOC.H>
2 ^/ N$ Z( w! ]; V9 D$ \int main(void) - _* B9 k& d, w! e- W! a
{
1 Z3 j* \& M7 g7 w/ T9 }8 ichar *string1 = "1234567890";
/ x5 R2 \" w2 }5 w0 [. S% vchar *string2 = "123DC8"; - m: n) N$ K' L! U4 q
int length; 
) r2 N5 C2 g+ x2 D% wlength = strspn(string1, string2); - O1 b" x2 \9 [# w" R
printf("Character where strings differ is at position %d\n", length); + e0 |; z: W U: v0 {5 m
return 0; 4 ~5 e+ L' D, Y
}
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, }( y. Z8 {) f1 M
函数名: strstr 
3 ~+ J: q: h; X, u) _: @功能: 在串中查找指定字符串的第一次出现
0 r* u9 P% k; u5 g用法: char *strstr(char *str1, char *str2); 7 R# E8 O5 h. R d
程序例: - L: K# w" A; w6 A
#include <STDIO.H>* k5 p' Z% H2 k' d' {) V
#include <STRING.H>8 p4 A) `8 @8 D8 }% u" T) E5 ~) r% u2 A( d
int main(void)
) Y- t6 t1 c, }{
" ~+ Q+ S% @3 U; V. E$ Z( bchar *str1 = "Borland International", *str2 = "nation", *ptr; 3 [- T9 T* b/ [* U: s' D
ptr = strstr(str1, str2); * _4 M) g4 f: }3 q+ f1 J P
printf("The substring is: %s\n", ptr); 9 t1 z/ R! F2 n5 g4 _& y* q
return 0;
+ C. R M& B- a4 z1 h5 L} 
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8 c( ~: q% [+ y/ i# c* |$ m7 C5 c) \7 @6 B6 w9 V
函数名: strtod 
9 s! m; e4 m9 i6 Z% b" J* p功能: 将字符串转换为double型值
7 B0 b- t% m" h2 i) |& S1 [- j1 o用法: double strtod(char *str, char **endptr);
0 b: D" E0 V9 o" J+ o0 N程序例: 
, `( K5 U: e2 o2 k% b3 y- z#include <STDIO.H>
. X0 t J7 z, F8 N+ p#include <STDLIB.H>
! _2 Q; I) R% }int main(void) 9 O2 D+ ~: d: o5 f" A1 D# J3 m
{ + V. F2 { X% k0 K" f2 C3 U
char input[80], *endptr;
3 o. s9 i7 a/ l2 O; w7 c5 odouble value; 
/ T8 p/ Y: l) x1 a6 X' sprintf("Enter a floating point number:"); # N3 I, L: e4 o/ v
gets(input); 4 e" ~/ O( _8 r8 d. m1 p
value = strtod(input, &endptr); - z& Q& `! q9 ^" m- A/ \! [& a+ l
printf("The string is %s the number is %lf\n", input, value);
6 d4 G9 Y, O% j, Lreturn 0;
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7 i% J5 ]. R6 F0 {; r

1 ^1 O; ^+ E$ N. E5 u6 T- o' j函数名: strtok 
5 d. s. l! Y! e; ~* X功能: 查找由在第二个串中指定的分界符分隔开的单词
6 r) C: ~" s( F用法: char *strtok(char *str1, char *str2); % G0 O- Y! p, q: P% a1 ~& n
程序例: 1 {3 T% e' ]7 A( A- [( t d5 t
#include <STRING.H>' h$ y, W Q9 m" Q% ?: C
#include <STDIO.H>. F" _( P% x& O: r/ d8 [6 C
int main(void) % b H$ |1 u2 B5 l. _. R# O7 J
{ , J* Z" }- S$ D) P
char input[16] = "abc,d"; * b3 _( y# c# q* I
char *p; 
; }& s0 j7 |+ F. a/* strtok places a NULL terminator ) o4 N- _7 m, J4 q$ h
in front of the token, if found */
+ s/ Q& [7 x U; j& ], h8 cp = strtok(input, ","); : c* R1 }0 w; H, ], s4 ^6 ^
if (p) printf("%s\n", p); ' W/ y4 `+ d% z! i9 N
/* A second call to strtok using a NULL
5 E5 i! g: i/ has the first parameter returns a pointer
 O& y) E Z U3 n! d/ _to the character following the token */
. `! B/ C6 B4 b xp = strtok(NULL, ",");
. p) A0 M- m1 H. uif (p) printf("%s\n", p); ) [2 l# K2 U/ K3 p m
return 0; , B% r# R7 D$ w; n, T' P
} 4 A! c r* U; I: V7 M
5 C& R3 @8 T, i

- D- B. ]+ H% K7 U. M# N9 S' p9 ^, g( T4 w+ H0 }: K# ~7 I
函数名: strtol 
# l: u* J( _& G功能: 将串转换为长整数 : U2 i0 ^4 s- B9 T" D: V/ Q8 Y
用法: long strtol(char *str, char **endptr, int base);
, y5 E& T; U+ D程序例: 
 q8 F' b1 v7 s. B0 e, q q#include <STDLIB.H>
" V' r9 J2 f( w' J+ d F#include <STDIO.H>
. y& F$ t8 \/ \6 q' z; r9 Qint main(void) % A$ ]/ J5 T2 A+ ^( _6 t3 L
{
; @/ O; k$ N3 j) q0 M4 X, p0 Gchar *string = "87654321", *endptr;
$ n/ U1 B5 G3 c' y$ clong lnumber; 
* O* } V) u7 q% q( A a" N% S/* strtol converts string to long integer */
" ?* w: l& }& Q; j$ r' {lnumber = strtol(string, &endptr, 10); - Q. p" J$ U4 B! b
printf("string = %s long = %ld\n", string, lnumber); 
! k+ H6 s) z! j' u! Lreturn 0; 7 w, e& x3 y Q* u9 [
} & u) @7 X5 ` y1 A3 c4 I' g+ l* Z
. C) f$ Y3 m" j
函数名: strupr 0 K& H9 a& j! b! a! @$ j) q5 P
功能: 将串中的小写字母转换为大写字母 # I3 ?* M- U; D9 z2 o
用法: char *strupr(char *str); ; P% c" b4 i, X; b. m8 v
程序例: 
* J5 R2 t% x/ A7 s/ F$ J6 } m#include <STDIO.H>
: i9 K& V7 O8 J; [. L#include <STRING.H>2 H+ N z3 S7 j5 A% D! W$ q
int main(void)
; j" L+ b$ j2 h* g. i3 `{ 9 }6 x8 d+ \3 r% A; R) f0 A
char *string = "abcdefghijklmnopqrstuvwxyz", *ptr; 
: b H) X% q" O7 X: X/* converts string to upper case characters */ 5 a* s' R( D/ V4 h
ptr = strupr(string);
/ g2 i ] d& ~" O# z5 ?" d* fprintf("%s\n", ptr);
; W) N! [8 n1 p# G, e, g9 {: _return 0;
 L* v' X) \& [6 Q; r}
! g }8 S) L8 m# b' x5 I# R+ c$ y6 t" R8 F$ ^/ E* z
& }. g P( {* |

; l k$ @0 Q8 i$ T3 }2 }8 [8 x/ s函数名: swab 5 L% f" n" c' v7 F) n5 J5 z
功能: 交换字节
, F3 M2 G& C( k8 }用法: void swab (char *from, char *to, int nbytes);
$ E K2 b' s& j& W# u程序例: 0 A( J2 w0 R/ ^7 P7 b" p4 ` J
#include <STDLIB.H>
" \1 l2 `: [# Q7 {' y#include <STDIO.H>
+ \: g! r0 r% E0 K9 V4 O% k% u; q#include <STRING.H>8 M* z9 Y+ N3 M! Q
char source[15] = "rFna koBlrna d"; . o/ J/ `! z0 j( ]) M3 k2 j" I% ^' n
char target[15]; " o' ?. d3 D( k- O1 U+ J# Z- H
int main(void) 0 ~+ F% S. ]; {
{ k; C2 f G% F' R! G
swab(source, target, strlen(source)); ; V7 S: e2 H; A5 E
printf("This is target: %s\n", target); & [0 r" f- L0 E$ Z+ m- D
return 0;
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& o: t: ]) R4 b9 E8 _8 N2 e: L4 @: ]" K' c5 j( W/ F; a) ?
# X" m% v, B# L2 x6 P* j7 `
3 m& {9 M: z' n* }
函数名: system 
! F$ k; ]" O, K% @# [7 i! ?% L功能: 发出一个DOS命令 8 k& S& m" R G, W! p, Q4 w. d7 u+ s
用法: int system(char *command);
& _9 Y7 V* u9 p/ v! _程序例: 9 n+ L/ U: F, B# E& E q4 `
#include <STDLIB.H>( f2 v- i& M: h0 Q
#include <STDIO.H># b' v; Y- s( B9 X/ e9 Z' c
int main(void) # N/ Z* f; C7 g; O2 h3 A2 @
{
! H3 B+ T: T; W& M1 F& N, d. yprintf("About to spawn command.com and run a DOS command\n"); ) |+ o8 v5 b8 L* Q; k% E
system("dir"); / P6 ?* {# B# ^9 B# v% I+ W/ i
return 0; ; J/ v2 T. f2 _6 Q8 F$ C
}