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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); " w8 e9 S& a% b! Q0 v
/* display the gray scale */
1 k) h( N. M* s. pht = getmaxy() / 16; : [, ~% l7 }! |/ x+ C/ W
xmax = getmaxx(); ' D! f) B1 d4 @% \
y = 0;
% E8 l. }5 @) w: zfor (i=0; i<PAL.SIZE; { 5 l3 O S, [2 K: r- n% S* w- @
setfillstyle(SOLID_FILL, i); 7 u6 ` M/ {2 E# x$ b+ F; Q2 j$ I1 b. @
bar(0, y, xmax, y+ht); - l) j* \ m# Q% S$ G
y += ht;
7 V: Q. r! O+ h} ; t# t& I" c; X# _9 S
/* clean up */
( f1 n3 G( y. T L8 tgetch(); 9 [+ q* s4 o9 z( Q; u! a; \5 i' l/ G
closegraph();
$ l: F g" r0 [1 h9 dreturn 0;
, W" O% K( A( Y# h- z% u} + o2 g& q5 p' [6 I

$ o. P0 F+ Q! M' r( p$ i4 G2 l/ C5 C" J# {' v
2 Z* b4 l9 ]% \
函数名: settextjustify 
* J$ k* k$ ]1 X% b功能: 为图形函数设置文本的对齐方式 # x' W8 ~( @" ?0 p3 }- i% a
用法: void far settextjustify(int horiz, int vert);
1 n1 M- e% ?( t" i程序例: 
) J: b" Z/ f* X6 g8 V+ l5 v#include <GRAPHICS.H>. Q& f! f% S$ J* q- L
#include <STDLIB.H>
& A) e. w2 j% x5 w0 P#include <STDIO.H>
' @2 h- C0 s4 f2 o1 z% i0 A#include <CONIO.H>
8 w8 C$ y# x2 V; }1 d: [/ v/* function prototype */ 6 U! y, V/ m# z. K" z
void xat(int x, int y); 2 n0 U8 U- C% I
/* horizontal text justification settings */ . v; W0 Y- O- x4 s k7 T3 w- ^/ k
char *hjust[] = { "LEFT_TEXT",
* d3 d/ b. H& b2 H0 x"CENTER_TEXT",
+ {; z2 H h8 p( s1 S"RIGHT_TEXT"
0 }. P! j" }, h) `1 w! O}; 
4 b" W9 t5 S# W6 a4 p' |/* vertical text justification settings */
! {; Q9 N; ]/ [2 r, e5 Gchar *vjust[] = { "LEFT_TEXT", 0 G% ?) }# S& }, g% Z
"CENTER_TEXT",
9 O# v% ~) A p9 e: L"RIGHT_TEXT" 5 r3 p8 `# l, P0 P5 T
}; 
 M4 D* r5 H/ W! f7 e2 pint main(void)
4 J! q: q0 o6 M$ j' R- s2 y{ $ ?2 G0 u1 S+ @, c& n9 D* k0 d! ?
/* request auto detection */ . o0 B5 \- U& U+ ^% }
int gdriver = DETECT, gmode, errorcode; " n0 a. A& U% u+ V' z- {2 P
int midx, midy, hj, vj; ; U; ~$ C: e2 J5 w3 ~
char msg[80]; 
( a5 i( v5 {) \ G6 B/* initialize graphics and local variables */
( o O% ~7 a J/ U: winitgraph(&gdriver, &gmode, ""); + d, w# \! E. S i8 w9 k
/* read result of initialization */
: Q( [3 }0 w7 O, c. w1 eerrorcode = graphresult();
% P1 k; D. H! B5 V+ [* _6 D; Sif (errorcode != grOk) /* an error occurred */ P7 k( c# ~" {. w$ {. G1 i
{
8 z# f/ W' d# R: ~2 A) m: k+ mprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 7 w; l7 [* B4 @
printf("Press any key to halt:"); - s; D! r9 k+ z$ D* h
getch();
+ ^5 o% `! V. \exit(1); /* terminate with an error code */
8 x+ f: Y2 o* G6 n8 E. C1 i} 
2 G5 w3 t( r1 k& j8 xmidx = getmaxx() / 2; 5 ?7 G; C" v4 d ~# C6 H' s
midy = getmaxy() / 2; `: @1 H* q g: A* r
/* loop through text justifications */
 ^8 f# {3 [2 T, H: ]3 ^: }2 I! k: yfor (hj=LEFT_TEXT; hj<=RIGHT_TEXT; hj++)
1 i' l( n5 @0 x! r9 yfor (vj=LEFT_TEXT; vj<=RIGHT_TEXT; vj++)
6 k4 B! k* Y8 a d' c( W{
' B/ N* j) d. e) y E; N5 lcleardevice();
2 }( ?# G' z9 W. L& ]* u/* set the text justification */
8 s/ |3 \ i+ g( t* k6 Msettextjustify(hj, vj); 
" U/ Z0 b) h4 F9 O& |) c$ @) i: G) L/* create a message string */
 V0 ~3 ^, L& E, s& ~8 s) K* R1 Asprintf(msg, "%s %s", hjust[hj], vjust[vj]); , M }% K( k3 i+ l
/* create cross hairs on the screen */
) C G; d; N) g5 J6 t/ C( lxat(midx, midy); 
' }& }! e" D9 A: G. B2 ?% ?/* output the message */ # Z5 x l# m) s7 Y, K1 F4 e
outtextxy(midx, midy, msg);
- e, w8 p8 o4 b" ` A- egetch();
& g: G, _) @1 X$ c} 
* Z: ?, q9 s4 ?( J+ f/* clean up */ ; d% {, k8 Z0 O5 |, I
closegraph();
/ Z8 I* V D' F$ z- Y! \1 M% S! Treturn 0;
. F4 O" z- a M2 u- p} 
& u9 I& u7 U! e# \1 ]/* draw an "x" at (x, y) */
6 F/ A% w6 [: W: Cvoid xat(int x, int y)
4 u8 c1 T( X9 f( ^$ ~, P{ % a% f1 y- h' Z" h; b# T
line(x-4, y, x+4, y); " C+ F- C j0 |5 V) Z
line(x, y-4, x, y+4); ( T2 p3 Z* p5 M9 W
} 
2 s4 v9 @% p( H/ a& `
( y# ~% k7 f7 S* F+ s2 _5 o
2 n, c, A6 e$ ~. b! n3 }" o- {" N函数名: settextstyle ' u% h. B& O; |) N9 |
功能: 为图形输出设置当前的文本属性
( s, Y& V' Y; J' V用法: void far settextstyle (int font, int direction, char size);
# B! B9 e! b6 z. W Z0 [; C* u2 P程序例: 
3 g" `* d$ ~6 b! v F- ?, M7 N#include <GRAPHICS.H>1 b$ ^+ T& Y, G: F) c; `/ a( f
#include <STDLIB.H>
5 }3 Z3 q7 S( {5 U8 I) v#include <STDIO.H>
& ]1 T$ m% A2 d" ]' l w: q" `#include <CONIO.H>& Q! X8 q' v$ ?/ q
/* the names of the text styles supported */
% Z6 B5 c3 f5 `) }char *fname[] = { "DEFAULT font", - o7 v# J9 [6 u6 t2 T0 h; z( G6 S3 x
"TRIPLEX font",
3 V, N" `5 c0 M: x"SMALL font", * H) \8 D, \0 j( c# M1 T
"SANS SERIF font", " s6 J8 l7 f7 E' L7 h
"GOTHIC font" 3 I; Z7 j; K" Q3 n! G( w& U/ S* s- B
}; 
- l0 R& }1 a0 ~9 B- H5 U( rint main(void) / v# @6 I& x; f3 K- U
{ 9 E1 `4 W# r) G, J1 @4 x0 m% E
/* request auto detection */
" j0 G4 Y) w. w8 Lint gdriver = DETECT, gmode, errorcode; 1 k1 o J7 Z7 {
int style, midx, midy; 7 g; E" B( ~; n
int size = 1; 
4 E9 |8 V' X& o8 `/* initialize graphics and local variables */ 2 n$ p$ u( X- ^. T: l5 }
initgraph(&gdriver, &gmode, ""); 
' r) H. x6 K# w7 W/* read result of initialization */
: \0 n& D* w* h j- k1 [6 }0 Serrorcode = graphresult(); 9 c" D! T% v5 k2 T: U# o+ w1 I
if (errorcode != grOk) /* an error occurred */
4 D0 L) E. J. K! P- o/ o{
$ x4 V, n2 z7 Q9 m. Y9 X. X1 h' ]! _printf("Graphics error: %s\n", grapherrormsg(errorcode)); $ a7 {6 e1 f" A- B
printf("Press any key to halt:");
9 i: u/ B- Q4 W4 x: a2 k" dgetch();
8 X! v) _/ n8 T8 j/ |1 x7 Mexit(1); /* terminate with an error code */
3 p2 M+ s4 h3 u7 Z} ' e% N6 e: u4 F
midx = getmaxx() / 2; w) K9 I' F# s6 U; n* T% V0 S
midy = getmaxy() / 2; 6 M6 [9 h6 m6 U M/ C
settextjustify(CENTER_TEXT, CENTER_TEXT); % {" b, {4 Y5 k1 R2 |
/* loop through the available text styles */ ) z( ~1 j4 k1 |* p9 ?$ ]7 R
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) $ T& ~- o( t3 b6 z' k
{ - ?" ?/ j( |5 t2 \
cleardevice();
' l# _) w: B: \8 S5 @2 G Xif (style == TRIPLEX_FONT) , W' j9 v- _' b1 `3 b
size = 4; 
" ?( a0 u+ {! |0 j ?/ w/* select the text style */ I4 Z9 S, h. |6 ^" S/ Z1 [) {, Q
settextstyle(style, HORIZ_DIR, size); 
6 K( o* V/ L* Q& ^2 A3 F9 I! E! L/* output a message */ " Y7 n" ~; h) J+ w/ w: J2 |
outtextxy(midx, midy, fname[style]);
; c: T& L, o) m+ {getch();
; ?/ o3 ]1 C+ G0 N, v ]( F' j} 
6 w0 b8 p; r" g4 V( a/* clean up */ 6 _7 a) T! ^5 h1 k
closegraph(); , F$ f* C# L Y
return 0; 0 v, V; J' ]! J' {, t
}
6 s8 r/ |% Y8 r# n+ g, U, w o" ~5 h+ H. G% e2 y
, R8 Z _0 a2 [: {. Q
函数名: settextstyle 
! Q. l; y! U) s) u0 N# G功能: 为图形输出设置当前的文本属性
( h5 T) l1 w0 R! x用法: void far settextstyle (int font, int direction, char size); 2 j: S# j4 O% A. x& A* Z7 i' w+ X" C
程序例: 
1 U Y0 r% s. J- ^#include <GRAPHICS.H>
1 N3 J6 i8 x" d! W( O#include <STDLIB.H>
+ f' \& g9 b) u% a3 G& O0 R#include <STDIO.H>
1 j! `7 P! ?3 S! ~#include <CONIO.H>
* Q# S. z" f# g: u# x1 n/* the names of the text styles supported */
6 ~2 s! `6 c" G2 \' F4 s$ K0 uchar *fname[] = { "DEFAULT font", 3 w- ^0 `6 s( C- }5 W. A4 K
"TRIPLEX font", ) x u8 Z: C7 V; G; w
"SMALL font", 1 y* K& S$ m9 B8 I
"SANS SERIF font",
! f$ }. }+ P- M& @"GOTHIC font" 8 t# {4 |. \. a
}; ' D' R8 u) K, b/ @
int main(void) 5 y; i+ S8 M: C7 q; J: Q( x Z% @! X
{ ; n, H& d; a3 K# b; _
/* request auto detection */ 3 C0 I8 w5 G, v' Z" t4 t
int gdriver = DETECT, gmode, errorcode;
7 x" e+ u- i* [( I9 Oint style, midx, midy;
4 E) X" m- ~/ b' y" ^7 ~) |int size = 1; 
& {5 ^! l# g0 n) n( E! c/* initialize graphics and local variables */ 5 U$ I+ n- `5 `6 q" e3 H
initgraph(&gdriver, &gmode, ""); 
! T, Z* O- |7 A- Q7 S/* read result of initialization */ " B2 _- l i; \
errorcode = graphresult(); / r s! Q( X) k. \9 b( c& ^5 l
if (errorcode != grOk) /* an error occurred */
! y+ [3 v+ v+ G9 `1 K{ . y5 _7 ]% F/ m, X B
printf("Graphics error: %s\n", grapherrormsg(errorcode));
8 g2 Z4 `: U$ o/ k$ r# O* J+ ^* S" fprintf("Press any key to halt:");
7 {& h8 R# p/ T/ ^$ }( J: Igetch();
2 P% v4 r1 _6 K3 \7 f9 Kexit(1); /* terminate with an error code */ . P1 S% S, J, Y& G/ v
} " N+ S' v' @8 q q
midx = getmaxx() / 2; 9 u0 \7 b( f) R, u: R) k& K
midy = getmaxy() / 2; 
* ^" Y# ?- Y. |8 Osettextjustify(CENTER_TEXT, CENTER_TEXT); , h g% ]$ y% p: ^5 F% ^
/* loop through the available text styles */ % m4 s& f/ E% L) K* K' M6 p
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) * m# t5 ^0 M( a$ w, |
{
! k7 S. s8 d& t4 P- i" Pcleardevice();
4 j1 k, q+ f6 Yif (style == TRIPLEX_FONT) * Y' H( G1 U) H. G7 e
size = 4; 
" g2 x: l c: q; M, M" C5 n& ~/* select the text style */
( }# h8 M& M; h" P. N- Hsettextstyle(style, HORIZ_DIR, size); 
! J- a4 z* g" d) ]7 V9 u* \! N/* output a message */ - }- w" u- L A0 V
outtextxy(midx, midy, fname[style]); ) D! c' O! q8 \2 L
getch(); 6 U$ J7 F6 H/ a2 b
} / @$ ]+ P1 \$ W/ B! c0 A
/* clean up */ , M9 F+ r: D7 g3 L
closegraph(); ; x" F) K9 l" ?% b' r7 b1 E; [
return 0; % N0 x0 F' I& f# W( N2 n
} 
" Z+ X1 R' e+ N6 ^- k0 r* |+ f
. D( T9 u& h: |$ a+ W7 Q
函数名: settime : ]4 p& b2 M0 c* H: o3 ?* w
功能: 设置系统时间 0 N; h7 q, U0 I0 z' X6 i
用法: void settime(struct time *timep); 0 r4 C0 H4 U9 }
程序例: 
4 s# d& }5 k/ T( A3 [ [1 o$ T4 L#include <STDIO.H>, I @8 Q1 [: W9 ]0 ~& P7 I
#include <DOS.H>
. r, Z; C* L5 i" n; Rint main(void) 5 u2 A8 ]* _$ N
{ 9 S' h& e7 [) O" U
struct time t; 
 c& C! }% o' c' V% g! o, V* Bgettime(&t); $ ]0 j1 F( p# q
printf("The current minute is: %d\n", t.ti_min); ) }, y$ V, a1 W8 @% q$ l
printf("The current hour is: %d\n", t.ti_hour); . ?8 U: [( ]# v) [( u9 t j
printf("The current hundredth of a second is: %d\n", t.ti_hund);
, }) ]& `# N* mprintf("The current second is: %d\n", t.ti_sec); 2 c; T# Y: E# d/ t. N
/* Add one to the minutes struct element and then call settime */ ; W: p/ {, Y: w6 z( k
t.ti_min++;
2 H; Y, v1 I/ v2 Q3 Y# ysettime(&t); 
, l1 s: [, r. L: f$ xreturn 0;
$ S" |3 w8 r- f( y5 T3 c9 E. V} 5 p0 O" A; c: d: C4 Q* P } x

% T( I7 F( S8 b+ K
$ E) p9 ~/ u" X4 A函数名: setusercharsize 
8 x; T, C3 t. ^7 ]0 I功能: 为矢量字体改变字符宽度和高度 9 u# w3 g# V, R' }* K" e1 O% ^
用法: void far setusercharsize(int multx, int dirx, int multy, int diry); ) ^9 u) `; ?% |% d8 A# W
程序例: ' G' ^% ^9 k' | S1 G+ j" G( P
#include <GRAPHICS.H>
1 f1 Q! P1 G3 R4 R- n$ I& A1 X2 M#include <STDLIB.H>
7 P# V2 F- a* ^#include <STDIO.H>
# m: [1 d8 _7 z% X1 N# o#include <CONIO.H>! }% J* ~2 W: Q" E- N8 a+ _! w: A
int main(void) ' \, d/ J/ K7 R) e" r2 D# M. \+ K# s) v$ L% Y
{
' K6 f/ F8 Y; k# M# }/ ]3 w/* request autodetection */ " x }1 z: ^! T( n3 o* Z# f
int gdriver = DETECT, gmode, errorcode; p3 e( s" X* d3 y) T* _; G
/* initialize graphics and local variables */
! C' l! P$ j! l [# minitgraph(&gdriver, &gmode, ""); 
0 z6 M8 |3 z" g* o8 I! |% J* [/* read result of initialization */
+ ~" O/ s* p N" S$ Qerrorcode = graphresult();
1 u! J' c" U# W E6 b% r: y) K5 [4 Qif (errorcode != grOk) /* an error occurred */
9 t! u! T# z# `! K- P3 d7 ~{
; q0 ]# O2 T+ M8 G& Y+ dprintf("Graphics error: %s\n", grapherrormsg(errorcode)); * f' C/ P2 x4 r2 L$ b
printf("Press any key to halt:"); # {1 O, e* A8 J
getch(); & k% ~ f" j4 n* }4 N
exit(1); /* terminate with an error code */
" F& i8 w. m( j* \& ~} - T1 k S$ H" M1 | M
/* select a text style */ & _* I: {0 \ G0 R! ^! l
settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4); d( }' b8 ]5 u3 N4 k X, |
/* move to the text starting position */
, O0 u$ ~( P! \& |6 h. cmoveto(0, getmaxy() / 2); 9 U% f+ K% A& q2 @' D: w: a6 j. s% {* F, r
/* output some normal text */ ) F. f) [9 ~. e
outtext("Norm "); 
3 X( y. G$ X/ h1 Y7 Q% S- B/* make the text 1/3 the normal width */ 7 w' |8 f9 _5 g V8 P
setusercharsize(1, 3, 1, 1); ' v: n1 D4 @+ ]. }
outtext("Short "); 
9 J! V% [% z7 D5 L+ p) s/* make the text 3 times normal width */ * Q! ]& L$ G# f, I0 M7 p
setusercharsize(3, 1, 1, 1);
) p" C; k! g: p6 T: Bouttext("Wide"); # O3 \: ~. ?8 v6 E
/* clean up */ ! _% [2 M& R7 s$ X
getch();
; l* n% N' s( [) x+ Z. Q8 [0 [closegraph(); - P5 Y# t( P9 p) s! Q
return 0; # M. h, m" c6 T) P D" S
} 
$ {( q- [+ j" V2 |. t9 B9 u' e0 P9 M# U% m; x& c
函数名: setvbuf ) r1 A2 a* F$ f. y% D
功能: 把缓冲区与流相关
: A4 D' F, `7 e9 t+ w/ y5 s! q. r! m用法: int setvbuf(FILE *stream, char *buf, int type, unsigned size);
1 I5 G. |2 l( u( U程序例: 
- S& J/ f# J, u$ D' z#include <STDIO.H>4 D4 u0 Z1 r6 c) ~8 f4 u! Y
int main(void) 2 Z& G8 w1 `, i* v; A' l, S
{ 8 e, O4 _1 ~# v3 I
FILE *input, *output; 8 I: R: N: z+ w5 a
char bufr[512]; " n; l# D" e v9 B: u- Z
input = fopen("file.in", "r+b");
2 \$ p/ Z9 j* k/ Goutput = fopen("file.out", "w"); ) P: y4 l' S& F/ y1 K
/* set up input stream for minimal disk access,
' k/ O: @* i1 p2 f! Cusing our own character buffer */ * R Z- w; {: y( m: _/ u; N
if (setvbuf(input, bufr, _IOFBF, 512) != 0) 2 K' o6 F0 M% @4 | h( ?" P
printf("failed to set up buffer for input file\n");
+ `" z( d, \/ T7 Velse
7 y, v ]+ E: P/ e( lprintf("buffer set up for input file\n"); 
, t. g- k: u$ S g- n5 Z: L/* set up output stream for line buffering using space that 6 M3 T U2 W( l2 X
will be obtained through an indirect call to malloc */ # k2 l" y+ W: p0 E8 d
if (setvbuf(output, NULL, _IOLBF, 132) != 0)
/ q+ Q4 _# l9 x' rprintf("failed to set up buffer for output file\n"); % L' Q, a2 ]" d7 [ B2 J& ?
else
( w) O" \% N% e1 k' _6 tprintf("buffer set up for output file\n"); 
" ], C8 V8 `- r; C: f' O" u/* perform file I/O here */ & Y |6 ^7 v9 J+ R% l) _4 M- L# R/ w! f
/* close files */ 4 e. V4 ~' g* b
fclose(input);
! ^ v1 I/ @) K0 q& Jfclose(output);
. V# o1 m- O5 N; @9 Jreturn 0; 5 q6 s, o1 ]3 r q" i- w% _- E4 S
}
 E0 v {/ @- L( W+ r/ l. S& {4 t( |+ n* U8 x

8 T' g) r/ j" `! _6 E9 G9 G! H. V" Z; O
函数名: setvect 2 K& r8 A' I# U7 H8 W3 u
功能: 设置中断矢量入口 - k# w* m g- }8 e+ J
用法: void setvect(int intr_num, void interrupt(*isr)()); % |3 t/ F9 B* a4 ]4 A. u8 ~
程序例: 
* j- }3 @0 g2 \- J( j, [/***NOTE: 8 v R. u; i; _( D& k& _
This is an interrupt service routine. You can NOT compile this ! F+ C" |7 [0 W" R* z. u
program with Test Stack Overflow turned on and get an executable
8 o5 M# C1 ]1 k" Y' b" J& Xfile which will operate correctly. */ ; x1 e8 Q9 q: } k+ A/ l
#include <STDIO.H>
' R$ D0 N) `( R9 E/ b; u3 @#include <DOS.H>
8 f* K9 I+ \* F9 S) X#include <CONIO.H>- g1 y9 x1 X4 M# [1 R8 y ]( t! I
#define INTR 0X1C /* The clock tick interrupt */ 
2 j y7 i" C0 H" {# @# E0 bvoid interrupt ( *oldhandler)(void); 
5 G$ h+ A) [( O# @0 i0 Bint count=0; . h7 z. Q' B6 h' f5 ^. L
void interrupt handler(void) 7 r) ^+ m, k( b% z5 c5 O( X: U, u7 H
{
) K5 \, T$ _) M) \/* increase the global counter */
/ Z1 _( x2 e4 s' b2 T" u, h7 rcount++; * U9 L: h6 V; ]* T
/* call the old routine */ : H! L6 c/ w8 {4 U
oldhandler(); 2 ` m# V6 {& G$ s. s1 m& m* D
} : A6 Z1 F: K+ v# f9 t! P
int main(void) 5 M8 U. l& r1 v- k; W
{ ( w2 x" u; v7 I. G
/* save the old interrupt vector */
+ b) D0 {; A7 E- D+ b1 f; boldhandler = getvect(INTR); ' c: W! d' T8 B$ Z1 j/ S
/* install the new interrupt handler */ & [5 U; `3 K$ u5 S+ z7 g# U$ g
setvect(INTR, handler); ) y) O1 \+ n2 {" L1 F
/* loop until the counter exceeds 20 */ 1 F) m. J' |5 E0 Y" g8 M! f: G* r) S
while (count < 20)
8 j* Q6 u% _* R$ h; L# {- P/ gprintf("count is %d\n",count); 5 ~5 C4 d: a9 k- d; o4 W
/* reset the old interrupt handler */ 5 r* D* S% V9 ~5 c) t6 Y+ t' d
setvect(INTR, oldhandler); ) a5 F! f) v0 K% }/ D1 r; K7 l) u
return 0;
9 k5 V/ q1 x& p& z6 C N} 1 V0 H! k- n3 }
; O' J' x# n$ k5 P/ q7 [$ G& z

* a; ~- Z9 M) ^5 X0 D$ Z" D函数名: setverify 7 }: {- g. G- g( k O2 N
功能: 设置验证状态 # N" z0 |0 c4 G. ]0 S1 d& F# I
用法: void setverify(int value);
5 I7 W9 p, J( _5 N/ A4 q程序例: 
0 l7 m: j! P% o#include <STDIO.H> z# `1 ]/ |6 l9 d* B0 y
#include <CONIO.H>
5 l8 | g: q% I+ E: Z/ d& K#include <DOS.H>. k" |0 m0 x& E; H& b+ e
int main(void)
' [8 V( o. e' T1 [5 W{ . M7 T8 X1 `/ ?8 \
int verify_flag; 
2 j( L1 R$ ]7 Bprintf("Enter 0 to set verify flag off\n"); 4 m& P2 j# y* I5 f4 X! l$ n
printf("Enter 1 to set verify flag on\n"); ; l1 D9 a0 i5 O# X
verify_flag = getch() - 0; / f( ]6 m# W# O3 J4 ^/ P6 l. k# }
setverify(verify_flag); ! ?, B* t$ y$ C+ J" F( N" s8 p3 Q
if (getverify()) " x$ w9 ^* Q I* e0 r
printf("DOS verify flag is on\n");
; C) K m' a1 }3 w9 M+ `3 |5 \& u( Delse 0 a: F) A: e7 C' h. Y; ]- X
printf("DOS verify flag is off\n"); 
, d& @$ Q+ ~" Creturn 0; : C" v8 G3 s' _3 s6 Z8 r
}
' l N+ u; F6 X! j
4 b. n- r- J, {. }/ ^# S) |3 g& a" W* M& j
函数名: setviewport 
" V4 A4 _, I+ R, p3 g3 M功能: 为图形输出设置当前视口 # @$ P6 t( v5 e# Z; T
用法: void far setviewport(int left, int top, int right,
5 J7 g5 M9 B4 E. \& l7 Aint bottom, int clipflag); 7 |& j7 [5 O# a' q2 W
程序例: 0 \: Y" Q2 D" U0 s' b
#include <GRAPHICS.H>
8 W- z1 o$ O/ {* |. ~" N. {# h' K#include <STDLIB.H>3 l R( ~% B/ Q
#include <STDIO.H>- B2 c1 T! L3 K9 {! {' d; A9 w
#include <CONIO.H>+ v( P( _8 N. [3 M' S
#define CLIP_ON 1 /* activates clipping in viewport */ , `6 y5 Z* [. p! D# K+ V' C4 w
int main(void) ; N: e# C) O8 ?9 b
{
/ h" c+ x$ c: S) T7 [/* request auto detection */
; b7 h* O: H4 C; x0 Z8 Hint gdriver = DETECT, gmode, errorcode; ! r+ e' x s% F
/* initialize graphics and local variables */ ! i7 z3 _5 m9 L. v: Q: E
initgraph(&gdriver, &gmode, ""); 
* r. O! T; r9 k- v. m$ M0 G- t8 d/* read result of initialization */
4 Y5 X" P3 ~2 P" ~( a4 Ferrorcode = graphresult(); ( l/ I9 H% [; n3 h
if (errorcode != grOk) /* an error occurred */ & p: Q+ c$ R/ M4 T+ k, V
{
4 {4 A( ~% w/ m) q2 t% C; `printf("Graphics error: %s\n", grapherrormsg(errorcode));
7 V- v: H: [% s- ?( bprintf("Press any key to halt:");
8 G: L3 g+ f" ~* Q: F7 Mgetch(); % r$ I: @: g4 d6 a
exit(1); /* terminate with an error code */ 6 [ _" s) f1 Z. `' L9 b' H
} 5 ^' K; A$ D* {, G" I( L, K
setcolor(getmaxcolor()); & }' A: N/ y z: ^' W! R6 b# }
/* message in default full-screen viewport */
( k8 E A* W. y' pouttextxy(0, 0, "* <-- (0, 0) in default viewport"); # ?) q* w+ J C/ L$ }) Q1 _" f
/* create a smaller viewport */
, `' c$ y- K; o/ [8 t( Xsetviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON); 
2 X" }! o" P/ T' P/* display some text */ ' u# \/ b/ b( y, w1 ]
outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 4 V4 C6 J8 o: C, l
/* clean up */
$ U; v! \2 `9 l& @getch();
& q1 f3 q! f6 W; [3 s' y* K K1 |closegraph();
' }* A% C6 a9 r i; E% @0 g$ o' H- Yreturn 0; & V. I" P5 p) u
}
4 W# g! Q1 T0 J# |( d
+ e: z, |+ O0 h! ~* V4 X# H- r6 {8 t" c# B5 Q9 l/ t* [, J7 S% z# H
函数名: setvisualpage / `9 K$ Q" b% n8 W: T
功能: 设置可见图形页号 - w) L2 V: n' W1 x" B5 z7 E! _
用法: void far setvisualpage(int pagenum);
* |! A8 V, k. g# q! Y: \2 W1 C程序例: 
5 f- X8 d) l% S$ C: e4 @' R#include <GRAPHICS.H>4 X3 a7 _% i2 I. N7 V7 s6 C
#include <STDLIB.H>2 Z2 T; d: {+ j. ^4 G/ Z
#include <STDIO.H>
$ ~3 D$ i0 a! @#include <CONIO.H>- X% E( a1 V/ q
int main(void) 4 `4 A* r8 `% L* w5 ^) r
{ 1 Z( f+ X6 `1 {+ s% q
/* select a driver and mode that supports */
8 l. g4 k; D( P" ~/ G& m7 H/* multiple pages. */ 5 H& j9 E, G9 y
int gdriver = EGA, gmode = EGAHI, errorcode; 6 \" j+ B- u: O- _0 N5 e! J5 o
int x, y, ht; 
' }4 |8 I8 J/ s/* initialize graphics and local variables */
' B: d3 b% X- Z' Minitgraph(&gdriver, &gmode, ""); + L0 |) O! H+ X5 O2 v
/* read result of initialization */
6 w) m0 [) m* @! i$ Z3 _errorcode = graphresult();
 Z% o( h9 F( \6 r% Xif (errorcode != grOk) /* an error occurred */ W8 Z; S* N2 g( c% m( V/ L
{ 6 m C: n0 {1 E' U+ C
printf("Graphics error: %s\n", grapherrormsg(errorcode));
7 o% p( D0 `' B2 iprintf("Press any key to halt:");
9 M3 T: v7 ?4 `' K. M. g4 M& Ggetch(); 8 x' Y" d- ]% L+ A9 f2 G
exit(1); /* terminate with an error code */ + k) \0 i' I& ?2 \
} 
) K1 C* R+ w5 \0 _! n lx = getmaxx() / 2; " W7 b9 f/ G. j* p# I6 C
y = getmaxy() / 2; # X3 r$ }$ k6 [+ A* l8 A* l
ht = textheight("W"); * t# B; Q" ]7 l1 C
/* select the off screen page for drawing */
6 |; }) S( a$ i2 ], Q/ csetactivepage(1); ) }7 o: q! K. n! ^* n
/* draw a line on page #1 */
8 N6 l" I" G! n- ^! Uline(0, 0, getmaxx(), getmaxy()); 
 D& D! j* S4 Y% q$ \/* output a message on page #1 */ * k6 D7 b5 P/ X8 c+ l' S
settextjustify(CENTER_TEXT, CENTER_TEXT);
2 r, c5 t5 K) nouttextxy(x, y, "This is page #1:");
. D. i0 d' X& C4 [& `, mouttextxy(x, y+ht, "Press any key to halt:"); + a+ ?9 i! f4 U6 k; M4 I
/* select drawing to page #0 */ ; A7 {3 {- _8 @; r+ Y& m
setactivepage(0); 
7 s6 Y% f! p0 }/ f/ H$ O+ e/* output a message on page #0 */
5 Q8 W' ~4 u" A* J% jouttextxy(x, y, "This is page #0."); / d4 ~7 k8 Y; v$ i
outtextxy(x, y+ht, "Press any key to view page #1:"); ! ^) h/ @3 A9 Q, _3 ^; T. W; p
getch(); ! Y2 X4 N- s1 w( ?5 I! a& ]
/* select page #1 as the visible page */
, Z+ L; \. F4 Q5 |% G, V# Qsetvisualpage(1); 
" t- T T$ \5 h8 J2 I/* clean up */ " J T8 @, p% H
getch();
) d! }' Y: M- W+ A* g+ K0 I" w& y7 {closegraph();
9 \" R0 @! F5 p( \: [, J) Treturn 0; 0 g2 ]7 K( Y8 O# N
} 
8 T/ f* K9 J- P9 w, o( e# @3 N' x% p: t1 e
: A! i' ^. w8 V3 D) ?, N
函数名: setwritemode 
% f# G% c5 {8 m9 v- T, {功能: 设置图形方式下画线的输出模式 : M% Y5 a( S8 J% }1 `" d4 X
用法: void far setwritemode(int mode);
7 J! {3 _2 Q* n7 I% t o; t程序例: 
! `9 _5 d5 Q5 I7 D0 v8 Q' ?4 S#include <GRAPHICS.H>
5 `- z2 ^; T: ^' p4 _#include <STDLIB.H>( x r. _1 a6 F4 f8 ?
#include <STDIO.H>( Q* ^2 T, B9 N- P0 v
#include <CONIO.H>9 w q. e+ W1 v3 t& y
int main() ' s7 ?& x# K: s0 {" \* A
{ . B$ n" [( J! `; b
/* request auto detection */ ' F. A; P- c" y, ?2 o3 [
int gdriver = DETECT, gmode, errorcode; - D3 Z/ y% L4 v. w5 N
int xmax, ymax; # ]: `0 x1 W S8 _
/* initialize graphics and local variables */ : c6 R' q5 ~& m: \; d0 J3 f
initgraph(&gdriver, &gmode, ""); # e, Y4 r) a- P5 S
/* read result of initialization */
% ?3 O |. T& ^! u8 p/ u( Terrorcode = graphresult();
% j" H2 _4 E2 |& V! D# Lif (errorcode != grOk) /* an error occurred */ ; M4 E7 R0 b/ |- R0 j4 G, N
{ " H6 I- E2 [; k
printf("Graphics error: %s\n", grapherrormsg(errorcode)); 8 \4 D$ [, F+ n/ y. B f
printf("Press any key to halt:");
/ W, u ^" @! S. [getch(); k9 ^! y6 @+ e7 j) b! U
exit(1); /* terminate with an error code */
- D& X2 o: b! X- a} 3 m6 t/ I0 c2 t' D/ k% j
xmax = getmaxx();
0 i4 i7 @. J! J' zymax = getmaxy(); 
' t% e, J& X. [9 a- I/* select XOR drawing mode */ ' T& a. O3 { L9 y' C& d
setwritemode(XOR_PUT); 
6 ?1 x6 p- O+ r; v/* draw a line */ 9 w& I; [" t+ \! G# U. c2 G
line(0, 0, xmax, ymax);
! @0 y4 h+ P: R3 g; ^) \0 z: hgetch(); ' [$ X3 a& u/ h- d( [( g p& E
/* erase the line by drawing over it */
0 ^% Q3 [) E- [% s2 mline(0, 0, xmax, ymax); ! s' @$ e2 C& N6 a5 J
getch(); 
7 h) D' x: @1 d8 S7 |& w9 l8 v/* select overwrite drawing mode */
( S7 L9 H: j6 ~. ]# R9 O, O2 n* Rsetwritemode(COPY_PUT); ) j5 n S: ?2 _8 J( ]
/* draw a line */ 0 @$ j6 m6 q% }/ ]' d+ F1 i
line(0, 0, xmax, ymax); 0 s( \2 v$ e4 |' i% J+ k# B4 O2 V. P" t
/* clean up */ * I: W4 K, g# K9 t
getch();
: w; n# u8 M7 Wclosegraph();
' W% B- y/ q- I2 E, c- p9 Yreturn 0;
- W$ B$ @. h/ z}
, S0 q8 a5 n! _, Y# o# r# N/ A# `" O N/ \/ X, p: p# J2 \: B

0 D, A5 t' c) S2 `' b函数名: signal ) X* m- R( o; J
功能: 设置某一信号的对应动作 , h- m# i9 g& b/ w- B2 I
用法: int signal(int sig, sigfun fname); ! u. q8 l7 _9 Y7 J% M( e
程序例: 
, b$ S/ B) g3 k' e! ^; F6 v& q, X/* This example installs a signal handler routine for SIGFPE,
6 ^$ E' b- Z' l8 w6 \2 v f+ Lcatches an integer overflow condition, makes an adjustment - |& p' ?, r k8 g& j$ j
to AX register, and returns. This example program MAY cause : ~& u! @: c2 \4 `: O. M. A
your computer to crash, and will produce runtime errors
! n* M' @8 `& m8 H/ @4 U4 E( h5 Ydepending on which memory model is used. ! s2 K8 u! C' t) w1 T" p2 g/ s; D# [2 k
*/ 
) T! o. h7 N# j5 x7 z#pragma inline , A! u. n7 O1 C) X
#include <STDIO.H>
. \8 ~. R$ ~7 u( r& M5 r4 _#include <SIGNAL.H>: O9 U! K2 I j6 S# g0 T
void Catcher(int sig, int type, int *reglist)
' y6 A" c6 C; G" K; Y2 S0 a{
5 n/ |- g, K% u k' n# ?4 D% o+ B, Xprintf("Caught it!\n"); / u' o9 A* V. ?
*(reglist + 8) = 3; /* make return AX = 3 */ : V3 M7 M/ ]1 B) r) p/ Y
} 0 ~) z! u0 X G* g# p* w2 c( V. w
int main(void)
; C8 B+ U+ O0 r. A{
& g! g' B) w: H M4 M$ {signal(SIGFPE, Catcher); ( i: d/ `9 N3 B" c% p. ?0 n
asm mov ax,07FFFH /* AX = 32767 */
- m& B; y' m: U$ n* s$ X( Z. x Nasm inc ax /* cause overflow */ ! U0 A7 d7 X7 f- T; c v
asm into /* activate handler */ * ]/ e8 G' T( T2 ^- E Z; o
/* The handler set AX to 3 on return. If that hadn't happened, 9 x* W9 ]& _, n [. ~4 x
there would have been another exception when the next 'into' 6 f- }2 E' l4 k
was executed after the 'dec' instruction. */
# _/ S3 d4 D Zasm dec ax /* no overflow now */ " b* s) V" r0 o% t
asm into /* doesn't activate */
' f+ Q; Q* z6 f7 lreturn 0;
& W' r3 K" r( d* `7 `$ o# d} ( h9 l7 i; s6 P& f# J

5 R/ `9 u4 t+ U' h- \% v5 e1 e% s5 d; t) \8 |" L
8 x; Z" \5 A( X8 G
函数名: sin R% @# J2 u t0 r& k y
功能: 正弦函数
( ~0 X+ S: Y4 n+ [9 z0 }/ |用法: double sin(double x);
2 B. m) L; J7 \; M- |* H程序例: 
4 W$ m" z/ z9 B9 n#include <STDIO.H>
! f8 @9 e- C6 K: S4 Z; X#include <MATH.H>
# ?' u7 ?& v8 E/ L ?int main(void)
4 X. V% P& v, A, }" {{
' F) C! e$ b' ]: N9 K/ ~' ydouble result, x = 0.5; : B# n& d% F3 `' c5 q9 ]( F( m
result = sin(x); ?8 N' b9 a7 X% e
printf("The sin() of %lf is %lf\n", x, result); 9 @/ {4 ^, Q# K, L
return 0;
4 u1 m' C+ i& H) M3 n# N} 8 ~" F' B0 w" c! |- B* f! ^% ?
4 ]; V& j+ a+ n- p! x6 i- o2 u
1 z* ]4 W& T b2 T
函数名: sinh $ D- z; K0 { I! O8 i
功能: 双曲正弦函数 * L( S+ ]. `, K" p& H- x- O6 ~$ T1 }
用法: double sinh(double x); 7 V. m- i- N+ ?& }, J
程序例: 0 M3 _4 Y% Y2 _# [
#include <STDIO.H>. b( Q: O; J* V; Z. k8 ]' i6 H0 B
#include <MATH.H>5 r6 q& T" P9 W5 P: ?$ j( w
int main(void)
7 u/ v) A1 O) \7 b% ]) A{
- ]& C! B7 Q9 x- Y% F1 o' R' ?4 Pdouble result, x = 0.5; 4 l$ ~% r. @: Z* ~, Q9 S
result = sinh(x);
+ S' ~. M3 |2 |- N; k* S0 x+ Cprintf("The hyperbolic sin() of %lf is %lf\n", x, result); ' z. @" u7 F& h) w4 ~0 U
return 0;
5 Y* A' R1 C2 o* G}
3 h! a. \4 [" O# n$ x a7 C8 a% t+ J; _9 ]
1 Q; v7 g/ `. _9 R0 ~

9 \. [* ^, @3 u# \/ m函数名: sleep 
1 s4 M0 U5 s% C& a. n功能: 执行挂起一段时间
5 q/ }5 h* r" y' H# [( V, p6 }1 K用法: unsigned sleep(unsigned seconds); / d9 d) m; w$ ` ?/ x8 I
程序例: 
$ ~, R5 I+ g5 g#include <DOS.H>
! c# Z$ @ O* _6 \#include <STDIO.H>
# l! f- V' N: Z& B% E) {int main(void) / M. A5 i( ^ w/ W
{ 6 D) s' z) u g# K* M5 A
int i; 
& {+ k- i- S- B B3 p7 B. Bfor (i=1; i<5; i++)
3 I$ ]4 U2 l; G2 }- W- n{
2 F9 ?4 D& D9 E' E( wprintf("Sleeping for %d seconds\n", i);
1 [0 g$ a! p: a6 d; Msleep(i);
9 Z" \5 |& x* c8 Z( D' a: f2 s} , k/ L' n- ]1 Y5 n0 i
return 0;
7 u1 s' y5 B" u6 d# {- P5 Q} , n6 a: t! b! }. x W
5 ]9 e; X# T' C$ S$ o" A) o# u

# X# \, P6 w6 u1 L- P# d6 P: N, |1 M. B6 Z. n, R6 c& I
函数名: sopen ! |2 o0 Y6 t! `2 @. c& S$ X# d
功能: 打开一共享文件
3 u3 C! g3 U- J1 F5 {用法: int sopen(char *pathname, int access, int shflag, int permiss);
3 W# A- `4 b# [! f( q% p' z程序例: , J5 y' B4 B8 U7 |9 O+ T+ z
#include <IO.H>+ D) I' s6 l1 G
#include <FCNTL.H>3 o3 h ~2 f/ P; Q
#include <SYS\STAT.H>" U8 c5 I6 N- ~# b6 I' X
#include <PROCESS.H>2 i0 |) u s$ ^
#include <SHARE.H>1 g" G0 o# I6 w# O7 U; S; F `
#include <STDIO.H>
' f2 r7 B- N1 N: t( oint main(void)
9 j- G! j3 B+ S1 F+ w6 D# p3 Y{ 4 j7 [5 i7 Z7 n9 N' ?1 M* D) b
int handle; 8 g" u8 E7 u0 l1 J
int status; + T/ D8 S3 C" d$ F( n; P0 I
handle = sopen("c:\\autoexec.bat", O_RDONLY, SH_DENYNO, S_IREAD); + G2 O, f: r |
if (!handle) 3 N- f% q2 P5 f. t
{
1 F9 u+ r, u0 g& T" c$ fprintf("sopen failed\n");
% e/ a% A# Y, n# u* Rexit(1);
, M0 ]7 P1 E( [5 m/ r% e& T} 
$ A0 [! e5 ~' {% D1 V5 Rstatus = access("c:\\autoexec.bat", 6);
4 c5 R0 |9 M( v% F' fif (status == 0)
1 k! i5 P- H- U: a8 c- nprintf("read/write access allowed\n");
! P2 Z5 G0 Z5 D- Yelse
printf("read/write access not allowed\n"); : J* T/ ~9 w3 m
close(handle); 8 {3 r" e. `+ @+ g- [* H1 Q" U/ V' K
return 0; " _0 u$ }7 n( s& ? w' w
} a: U1 M Q% }9 k" q

- T: _0 n } B9 j( J& b
! K S' p# N, V$ N; s. V/ [% B" x6 G. z( k
函数名: sound 4 \2 e7 |7 f3 S5 G, T4 T
功能: 以指定频率打开PC扬声器 # p, N/ o: K4 u2 f% N# H" K0 J
用法: void sound(unsigned frequency); # B2 L4 ^- n4 Y( ^2 E3 }
程序例: 
* Z+ J' v' u* K( ]# x# `/* Emits a 7-Hz tone for 10 seconds.
: m( Z2 B: ? T# dYour PC may not be able to emit a 7-Hz tone. */ 2 N6 P9 q& C2 U
#include <DOS.H>
$ Q# R, r( u% x1 {! K$ g5 ]; Bint main(void) + n7 X! `7 T$ a, H: W% |
{
6 A9 Y' X" z) |; m' B8 }sound(7); ) H+ g( `1 J+ v' I6 a
delay(10000);
& z1 R e1 w& g8 knosound(); 6 h, H) S0 L( H" b4 ^5 C; d
return 0; 7 q# R' l! J3 u P
} 
: }5 M- `' r0 ?! t
( l. }4 z/ J6 h3 h+ J$ b- h6 C4 o2 z. ?
! m& @! r. `* v0 | C6 c" C! S T0 }( @2 K1 q
函数名: spawnl 
4 E% ?3 F6 j& b5 T- G6 f5 A6 i& j功能: 创建并运行子程序 " C/ }, l0 f1 [0 z5 D; o6 f9 }2 T
用法: int spawnl(int mode, char *pathname, char *arg0,
1 z8 O* p: A7 L' M; M2 Z7 Darg1, ... argn, NULL); ) u/ x2 @3 N4 w: t& L
程序例: 
7 e% s( }( M9 A' a( P! c#include <PROCESS.H>
4 t/ f9 h6 t* k( \4 {% O; p#include <STDIO.H>
" X: Q& y5 A6 Y#include <CONIO.H>
( U& ~2 ^1 N( C) r0 v0 S# J! j& yint main(void) 4 [1 p) p2 N- [, {' o) X1 [1 U) ^
{
% X4 a: U/ c& z( Oint result; 
) R$ q5 i% `5 Y1 f" Z; Y7 `clrscr(); ( z; R( y' h6 R# r$ [+ z
result = spawnl(P_WAIT, "tcc.exe", NULL); / c: L6 ?& w2 m3 T
if (result == -1) ! L4 Y3 l, K$ V; z
{
$ D0 y& D4 g& d$ dperror("Error from spawnl");
3 } J0 G7 b% Y" H# Aexit(1); ! d4 m. ~. G, o5 j/ S) D
}
' A- q" _1 f; ]return 0;
% c5 g& {: ^. T4 G$ K} 9 y& e1 u0 ?' v1 o# g
& l: _% \/ Y2 ^' H
/ `7 t# b5 ~& J7 x
函数名: spawnle % P2 D: [- v+ L$ {. y+ C
功能: 创建并运行子程序 + l8 V& C. `+ n2 _% K
用法: int spawnle(int mode, char *pathname, char *arg0, & v- ^# R* S: h v
arg1,..., argn, NULL); 3 s) {; b0 |& G) m
程序例: 
" {; Z2 S. |; k# J/* spawnle() example */ 
* ?" z( ~+ J) ^, I# s* o* n5 h#include <PROCESS.H>
5 P& H7 d4 Y0 B) c/ g2 V#include <STDIO.H>
7 s5 J3 c* A9 N2 |2 w: [' z#include <CONIO.H>4 J1 o( w8 W) `) q
int main(void)
1 o5 {% I; F4 L% P& f0 F: M0 z{ $ c8 E4 n/ |0 o7 z
int result; 
' t& `+ i. Y ~9 [: o: ^2 B) @clrscr();
( h3 Q: A8 u6 b! g2 ]6 dresult = spawnle(P_WAIT, "tcc.exe", NULL, NULL);
7 I! ^6 _% R/ wif (result == -1) 7 k* g+ K, S) N5 u2 g( l
{ b: C! b% P' w% A5 E$ f
perror("Error from spawnle");
+ K; N; _% W! B5 S( ~5 lexit(1);
% f* x$ ^8 w& y& N}
 g* z S/ c; y) Treturn 0;
& m( L* a0 A( d* |9 e7 H4 L} " p3 r% E1 f" I6 l! P5 w# T+ S
8 P% o& M6 N4 b

; U) Y% m$ c1 U2 N" }: L6 j% L) [
7 W8 _$ o0 W5 e- w9 m7 W* u函数名: sprintf * m. n- @2 W& |" g; i% J6 a1 ], f
功能: 送格式化输出到字符串中 1 S9 w, D: n% Q- m6 v
用法: int sprintf(char *string, char *farmat [,argument,...]); 4 f" @3 C9 g5 [8 z/ O& I- |* }
程序例: 
6 Y2 R9 _" f% \' u, S) K3 s5 E8 u* _#include <STDIO.H>
5 R0 u+ N7 C% M4 T$ l' E4 _#include <MATH.H>
4 _2 E# F. R7 C6 e; m2 sint main(void)
 p7 ^- }, h5 i3 G$ ~ F* Y6 D{ & `0 [2 U! t* F8 w
char buffer[80]; 
$ \/ f& e1 }6 b8 ~* wsprintf(buffer, "An approximation of Pi is %f\n", M_PI);
; q; r! a8 W( _; `5 [puts(buffer);
8 {" o& b& {7 F4 W$ W" Rreturn 0;
" w! V2 d# v' p% d. w7 q0 P}
( h, x, }2 Q& ?. D5 X+ d) q8 s9 V$ A+ o2 V

5 f9 \# ?5 C5 I0 W% w函数名: sqrt 
. _6 H% Z0 a6 X0 R9 K/ T功能: 计算平方根
$ ~5 E& R3 e/ E2 o$ i用法: double sqrt(double x); : Q0 b( ^$ [! ~ k
程序例: 5 }4 m3 _7 m$ ^
#include <MATH.H>
7 p9 z! Q; j- s+ h" T#include <STDIO.H>6 o; M6 ~9 {' D" Y% w
int main(void)
& I! p$ R! q& j% r" ~: G{ 1 s/ J6 T) x% V/ N7 `8 A& v+ p
double x = 4.0, result; 
- W+ Y ^) f: j9 y8 _ s" J u; yresult = sqrt(x); % c2 C4 b' T, r0 _/ s0 `2 G8 J( X
printf("The square root of %lf is %lf\n", x, result);
6 Y. k5 e1 ~* Preturn 0;
 \# F o+ T* g) o* u}
+ C3 J2 l& _4 K! D
0 z# X4 D& b. o0 j0 z函数名: srand 
2 G$ a8 o5 |$ r( k! k功能: 初始化随机数发生器 & C& U8 o0 y0 {$ S" e' t- d4 \
用法: void srand(unsigned seed);
9 \& \ R& z. [# {& X0 [程序例: ' v" A( [! Z( P3 B
#include <STDLIB.H>/ G/ |+ |! \/ R, Z3 h9 f, B
#include <STDIO.H> ]6 R# r; w. W5 E
#include <TIME.H>$ D7 g% L5 [1 H6 p& x
int main(void)
1 w$ ]$ y1 ?- d5 ]' b9 o6 h{ ( ?) V5 s/ [) h7 t3 [0 V
int i; : L \# Z" a; F& B
time_t t; - q6 J2 K7 E& p3 j& _
srand((unsigned) time(&t));
5 }' |2 B5 C% B% k+ F/ y5 K- jprintf("Ten random numbers from 0 to 99\n\n");
! v& S* Q' }5 v$ h9 sfor(i=0; i<10; i++) % ^+ j; a& y3 X/ y5 T6 s7 e
printf("%d\n", rand() % 100);
0 S* P, i7 Z9 j9 \$ n/ @1 Hreturn 0;
$ f6 L+ [5 L% `4 w6 P& I' K" w} & a# p7 Z5 W+ Z9 s5 n- Z8 Q

0 s$ E8 p9 {% O& P2 J7 Y
; p, H; B% q3 j% H% Z) ~5 x函数名: sscanf - J5 h X1 Y5 b7 n1 ?* c" w
功能: 执行从字符串中的格式化输入 ' y1 o1 b) u9 Z0 a/ ?. x4 `, l
用法: int sscanf(char *string, char *format[,argument,...]); 3 R9 W# _1 U- C; Y) t' Q
程序例: 9 T+ I+ @& X; A' N( \3 W# `
#include <STDIO.H>
: O# j3 Q0 v/ E% M% \5 x8 H( p#include <CONIO.H>% t" E) x5 `9 ]
int main(void)
9 C, B( C8 Q# X/ _: v{ 1 V/ C \5 p2 M1 c
char label[20];
2 s2 B! M& X1 N. I* w! m5 e jchar name[20]; # |5 [3 D" Q3 d0 U
int entries = 0; & w8 f* k/ K! {. x" U+ ]' _9 g7 v
int loop, age;
3 O8 ~2 g& @: Sdouble salary; 2 O3 t- x2 M' V+ D! m) D
struct Entry_struct + T2 [! O2 h) X% S: i% y7 }/ P+ x
{ 2 U7 U1 @+ @' g0 @
char name[20];
8 [5 n2 X1 N6 Y8 ^7 T/ n; Iint age; E7 F" R/ y# t# j" K' a2 @0 S# L
float salary; : c: q- }' p( q8 ]# \" E4 c& ?# O" o
} entry[20]; ! [1 G" _: Y- {3 Y m
/* Input a label as a string of characters restricting to 20 characters */
4 o/ `" _0 M) _9 X% Q4 Pprintf("\n\nPlease enter a label for the chart: "); % F% A( K' T, s j
scanf("%20s", label); % [/ g% G' U1 n0 y! K+ A$ U7 Z
fflush(stdin); /* flush the input stream in case of bad input */ 
5 A7 H1 \5 b6 i/* Input number of entries as an integer */ 8 o. Q8 a( g( m
printf("How many entries will there be? (less than 20) ");
* t: `6 Y( t( h8 s4 t8 ~" \scanf("%d", &entries); ( G" Y! O2 q. T' V& e% `
fflush(stdin); /* flush the input stream in case of bad input */ 
) j" I3 H* Y5 O3 L/* input a name restricting input to only letters upper or lower case */ ( A3 c7 x$ W& W+ F& q
for (loop=0;loop<ENTRIES;++LOOP)
4 x0 J* A& \$ a1 E$ p { + {# U- X, i$ o. u
printf("Entry %d\n", loop);
7 M! H9 J) V- k: c. F o) _printf(" Name : ");
$ n) B0 z( }( l( k0 T8 dscanf("%[A-Za-z]", entry[loop].name); 1 U, g% e8 y+ @( v: ?" y
fflush(stdin); /* flush the input stream in case of bad input */ 
$ Y( R! S' d7 o+ C/* input an age as an integer */
: a+ ^! L; ^# W: R7 hprintf(" Age : ");
& n# ^7 f" Q- K1 u# U8 Cscanf("%d", &entry[loop].age);
* |/ m1 j8 s& v7 k% Jfflush(stdin); /* flush the input stream in case of bad input */ 
' N, i4 r0 U$ s/* input a salary as a float */ 0 W1 P/ R3 |4 N" l0 X
printf(" Salary : ");
$ d, r) @ m, V( S1 m8 j- jscanf("%f", &entry[loop].salary);
* _/ @( w m, M" O H7 Hfflush(stdin); /* flush the input stream in case of bad input */ $ w% h% ]0 {( y2 s3 M& o
} 
- b5 X6 |* E3 Y" R; c; S/ m/* Input a name, age and salary as a string, integer, and double */
0 f# J5 p3 C7 b; `! eprintf("\nPlease enter your name, age and salary\n");
: n9 ` x M7 g1 m* ]scanf("%20s %d %lf", name, &age, &salary); 9 w$ w# m3 \5 }* H

, x# M5 Q; X% E/ f0 G4 ?7 j/* Print out the data that was input */
2 q- U2 _ n) }8 R2 qprintf("\n\nTable %s\n",label); ; @: `" `, j& a0 @" Q% J) x4 B, p
printf("Compiled by %s age %d $%15.2lf\n", name, age, salary);
7 W Y# t f4 Z* Q" j( yprintf("-----------------------------------------------------\n"); 9 J% Z6 B/ Q, t" J" Y" D
for (loop=0;loop<ENTRIES;++LOOP)
" ]6 B" s$ P3 l. S* @ i' s7 }7 l8 w printf("%4d | %-20s | %5d | %15.2lf\n",
3 U9 \& h3 X6 \8 P8 m: G2 C4 F2 hloop + 1,
/ H% h/ \' t! j2 {& sentry[loop].name, 9 s% ]* @3 v9 P- T1 b: R
entry[loop].age,
1 J: f0 O. O% U6 j- e( b# mentry[loop].salary); 5 e+ k0 i+ I+ s& ?9 ^
printf("-----------------------------------------------------\n");
% W% S8 b. O) h( E8 r" K4 breturn 0; 7 M# e% ?$ i+ E$ v
}
# L. w" I! W/ g q
4 k0 f& Y' @5 n+ Z- W( s4 j6 U* ~/ d) ]$ s
函数名: stat 7 ^7 u) Z" p% X: M6 _' ^/ E
功能: 读取打开文件信息 2 S& `! H' k/ s0 K5 N
用法: int stat(char *pathname, struct stat *buff); , G# z0 k2 w9 m8 o1 F# s( t x
程序例: 9 A! V; C7 X% x
#include <SYS\STAT.H>3 Z, S. m- `8 w: C G$ ^
#include <STDIO.H>
 u1 N4 b, b" p$ g* @. m5 z/ u7 M#include <TIME.H>
2 Z4 ]& p; L, _3 M( Z6 P7 K* {; G#define FILENAME "TEST.$$$" " w- n$ m$ g) [! T9 ^1 h3 F
int main(void) / a0 d, @# q6 D. v' |) y
{ 1 x k4 v- L" y7 y8 ~2 Q. N. C
struct stat statbuf; " n6 x+ I% i2 M% U9 e
FILE *stream; 1 K g3 u# l6 t) H2 `1 L
/* open a file for update */
. a! Y3 e6 T z% P% C3 w# zif ((stream = fopen(FILENAME, "w+")) == NULL)
* U# [# [; u, R; v9 w- A# Z/ ?{
" |, [' S# ]% W; e7 E5 G# E: Jfprintf(stderr, "Cannot open output file.\n");
+ w, T0 t. f$ x0 b( P3 }: oreturn(1); Z9 t- r f9 `" i6 S% k
} 
+ a( Y4 s3 T/ c+ r/* get information about the file */
, T1 ?4 R: _$ L- ustat(FILENAME, &statbuf); ( x0 Y F' n: j7 r, G R' c) `: e
fclose(stream); $ D! i b: J w0 T/ _0 F* V! w$ g
/* display the information returned */ ! ?4 x1 a/ j T# D1 o0 @
if (statbuf.st_mode & S_IFCHR) + {, C8 l$ T8 Y! |9 w# F; t
printf("Handle refers to a device.\n"); . u" _$ C* }4 k5 P5 [2 c
if (statbuf.st_mode & S_IFREG) " W2 \' d9 g: t& J$ _
printf("Handle refers to an ordinary file.\n"); 2 `, @2 W3 `# Y9 k
if (statbuf.st_mode & S_IREAD)
" z: [# v- z0 u( }5 k" Aprintf("User has read permission on file.\n");
 l9 H" P H/ G7 Y2 P! f lif (statbuf.st_mode & S_IWRITE) 3 c, E: E% f0 K' ?- c4 s
printf("User has write permission on file.\n"); _+ |8 c: Q7 o- P2 X1 ], x
printf("Drive letter of file: %c\n", 'A'+statbuf.st_dev);
0 Q% g8 }7 l- @6 i+ Fprintf("Size of file in bytes: %ld\n", statbuf.st_size);
* b1 z7 U% E; S+ A) o! vprintf("Time file last opened: %s\n", ctime(&statbuf.st_ctime));
4 ^" H2 [; b+ [1 Rreturn 0; 2 _& D Y1 ]' u; h% ?) A
}
+ D7 f: N/ \* e3 ^( f- C/ X6 M' h) A. @

: Z8 m1 W4 z7 O1 U) L. P3 a! _
* U X' E+ w* p* K; ?5 c8 d8 ^+ a函数名: _status87 
% @/ o" r7 v7 n4 Y3 d功能: 取浮点状态
1 L0 q+ H: X" M2 v用法: unsigned int _status87(void);
" ^5 W* P9 v" y程序例: 7 H: p: u) S. C, v
#include <STDIO.H>
6 E3 ?6 I8 T, v( u8 M8 l#include <FLOAT.H>
- T/ j7 }5 C1 r) |0 m% S; }int main(void) - S7 w4 k, H& ?* j% ~4 v' G
{ 9 Y4 T2 `4 I" I- y
float x; 1 [ C1 s0 H* F& {: F8 J
double y = 1.5e-100; , o1 _: Z: _: `; Q5 i% W) }2 l
printf("Status 87 before error: %x\n", _status87()); ! _6 i: U7 K# m7 a- s5 [
x = y; /* <-- force an error to occur */ # a3 C$ H. i! U2 L
y = x; 0 M( _; b; m4 W
printf("Status 87 after error : %x\n", _status87()); , T, Z1 l, H3 Z& ?( a9 I$ }
return 0;
% Y K( X1 l T. @9 ^$ I) x- C} * i6 x$ L0 ?* n4 @$ c
) n! h! d- c0 j8 b% n0 n
3 `" k) t3 ^7 S! U% G- \
函数名: stime 
8 C% Y% N% L$ I V功能: 设置时间
( m! R4 |/ p6 S* B; y用法: int stime(long *tp); 5 W6 R5 ~. f) K0 k
程序例: ' i0 c: L% o' X9 C9 u. z% y7 y* O
#include <STDIO.H>! r2 ]7 f# ^' D( P8 F4 F6 D* ^
#include <TIME.H>
) ^: ^) D& o' A7 K3 t t#include <DOS.H>$ c) I; c- E r& o. ~
int main(void) & P$ p" T2 f5 f; z# k
{ ( n% V. I9 F' Z# i2 O
time_t t; : w5 [0 w& t; u2 |) |- U
struct tm *area; : v! ^$ L& [8 E
t = time(NULL);
) v. w- |5 r; ?: V( a0 y& J9 Harea = localtime(&t);
4 U [2 i* i0 ?1 {& C! V1 Aprintf("Number of seconds since 1/1/1970 is: %ld\n", t);
' c/ y' [. t2 m6 F$ Cprintf("Local time is: %s", asctime(area)); / M* [1 }* y. l! y! E
t++; * N, j2 S8 R& A, H) q
area = localtime(&t); ( U( l1 Q! b! y, W, ] T9 H
printf("Add a second: %s", asctime(area)); 
- b: B! p+ x# I# J: Ut += 60; ; g" x) G) a* A1 j& }* X% b
area = localtime(&t); 4 j( Z/ X% J$ D' X5 i
printf("Add a minute: %s", asctime(area)); ( g/ \2 m: B6 @' [
t += 3600;
5 V$ f& K. j( g2 X- farea = localtime(&t); # `- D) n6 T3 h1 x
printf("Add an hour: %s", asctime(area)); & z9 G5 ], \: Z4 M( l5 G1 @- H
t += 86400L;
" d4 X( P* |7 I6 A5 ~$ q" j# Larea = localtime(&t);
3 e3 p' C- X) P0 D# J9 xprintf("Add a day: %s", asctime(area)); 
t += 2592000L;
" D8 \- n8 {$ varea = localtime(&t);
4 u# R2 \" ^4 |6 Q" ^printf("Add a month: %s", asctime(area)); 
7 c3 r+ Z3 [9 L8 _. ?, \t += 31536000L; % J0 Z% ]; o7 G1 d1 p8 ?! J6 G/ S
area = localtime(&t); ; m: H# o% m) m+ L
printf("Add a year: %s", asctime(area));
. F! i1 ^' P9 v \5 xreturn 0;
4 q) R3 k8 x3 C- d7 V3 Q$ C} 
, u" j% S/ p% V" F3 K8 F. @: K, s, w6 R1 J3 X+ c' W9 K3 h) N

; Q7 a4 F* W* S `$ ^1 g
 ?9 R& o4 O' \4 D& F& b/ k% J函数名: stpcpy 
* u- b0 b8 l- G' Q5 `' Y% s0 J功能: 拷贝一个字符串到另一个
+ O; p: ?3 g" i0 K7 P用法: char *stpcpy(char *destin, char *source);
: l, q7 C& Q3 x5 G' x程序例: # B( U% S) K! W5 }. I8 l. a
#include <STDIO.H>
- r0 T% {8 ?% A2 C0 I/ K ]8 _2 x#include <STRING.H>% j& k J3 g1 U; G g2 z+ l2 u7 ~
int main(void)
- K0 n, p! _5 C. S5 L" q+ m{
8 |6 c1 e+ V0 ]% h2 e+ l! fchar string[10];
( W4 O( U P6 B- t' h3 ]2 x9 \/ Bchar *str1 = "abcdefghi"; " K6 p% m5 L# N1 w$ L
stpcpy(string, str1); ' R1 p$ P4 k. F' L5 K9 H' K: L
printf("%s\n", string);
) H) V: i3 C+ {( areturn 0; 4 q! ]: D" M* n2 m
}
7 R- M2 q' U2 B5 D; r8 v4 q1 O, R
4 c. d9 ]1 E# b& ?: Y! n% [
. R& f* Z) o$ o% |
% s( K- [2 N: U8 o, W函数名: strcat . i: e# T8 `9 I5 L3 ]
功能: 字符串拼接函数 " Q: W7 ^ J( B3 y! d
用法: char *strcat(char *destin, char *source); & U- F9 K7 }) F
程序例: & l* T# u v" u( v( `" a
#include <STRING.H>
5 C- G1 d' S0 P8 J#include <STDIO.H>
0 r! \6 [- |2 }7 o0 \: Qint main(void)
{ 9 H1 g0 Z# v7 r: X5 R: h$ _; x
char destination[25]; ' r% P& Q5 J; ^- c/ ?+ V1 F* H
char *blank = " ", *c = "C++", *Borland = "Borland"; 
, {: d+ Q u1 x; J( E/ O3 Qstrcpy(destination, Borland); 5 S2 u- ?( V- U, u; S
strcat(destination, blank);
% w% d- @6 A, Q1 h/ [& I3 T1 l, G$ kstrcat(destination, c); ! a" L( I. o1 d0 a$ R8 ?; U- K
printf("%s\n", destination); + O, V0 x8 x$ q) h( W2 a# g l
return 0;
1 k! E# \5 R! w4 X7 z% d}
5 M* [( k% J2 b8 `0 J. b* d, c$ z/ K4 N+ _

: e/ H4 R- m* v$ {, W0 ^! N1 C
1 w2 x- s K8 c% e" |6 b$ H) R' D函数名: strchr 
 |% C i% ^' X功能: 在一个串中查找给定字符的第一个匹配之处\
! p# y. G( w$ \/ C+ K用法: char *strchr(char *str, char c);
9 T8 b9 e5 d- y1 _程序例: 
+ Q7 ^7 D2 b; ]! K B8 j#include <STRING.H>; p x) s% Z/ q; C
#include <STDIO.H>6 C4 D1 i/ w; ]" c: Y
int main(void) ) r) }. S# @. ?6 n
{
" J( X/ D; F c: ichar string[15];
char *ptr, c = 'r'; 
' g/ ^. i( @+ x2 V. M7 ^5 ~strcpy(string, "This is a string"); ; U( {, m" d& @! a1 v5 d# ]
ptr = strchr(string, c);
' _2 v& L$ b: t3 W' G _4 m: u9 rif (ptr) 6 y) S# w" y' E+ ~8 d+ [
printf("The character %c is at position: %d\n", c, ptr-string); ( ]8 O C) ^5 B
else 3 [4 ?) h# i/ w1 t S
printf("The character was not found\n");
8 M5 }4 E: c9 y, @ Greturn 0; & ?2 \$ ~4 M. p
}
( A+ h" ~5 x& t/ L5 \; f9 L# X+ s: I- u
: y7 v. c& M, v1 V3 _: Y
3 U- g1 h& f0 b5 h/ c/ c/ c
函数名: strcmp
8 r4 {! E7 b; C7 M功能: 串比较
/ x: x V& B" |2 ]/ a1 H& w用法: int strcmp(char *str1, char *str2);
/ m0 z; |7 L& V K8 @+ A: w程序例: % y t% a5 r L- i/ Y1 F2 t
#include <STRING.H>
# G+ y8 X; M$ J0 h#include <STDIO.H>
3 J: L; e5 m' ?int main(void)
" n- o0 ~; h( V. p* B$ A2 x{ 8 f1 o, ]9 Z- ]* P* O$ t
char *buf1 = "aaa", *buf2 = "bbb", *buf3 = "ccc";
4 l0 p4 J; m. R* I# D4 xint ptr; ( S. ?! y; ]# P C- j% C
ptr = strcmp(buf2, buf1);
 U% {1 P3 s8 F3 V% e; e* V( Oif (ptr > 0) 3 I \4 n- u5 Z3 b# E+ I- p" x$ r
printf("buffer 2 is greater than buffer 1\n");
( N, q( g' [# _- |# I0 o8 Y$ gelse
( g+ X% ~* k) y: t9 e- Sprintf("buffer 2 is less than buffer 1\n"); 
' a" F. Q U4 y) t0 t: B: x% Xptr = strcmp(buf2, buf3);
/ E( {( p L% A3 p- @2 C" x% Rif (ptr > 0)
) f [ ] ~% u0 t+ B) R9 M$ @9 rprintf("buffer 2 is greater than buffer 3\n");
/ h( p& H. Q0 }2 _$ Yelse : Q2 E% H5 N% q2 E0 Z
printf("buffer 2 is less than buffer 3\n"); 4 c( f1 s ?$ T9 P: _! k/ [
return 0;
6 b1 {# y( K. x; W8 r8 w}
; T1 B" D- `7 K1 _: Z4 ?. |0 w% M# U- P
+ H) f) e. s3 p# O+ \1 g3 C0 u

6 o1 c7 h8 [7 f/ T6 Y" F函数名: strncmpi - @' C3 Z. b# H2 U" b( G
功能: 将一个串中的一部分与另一个串比较, 不管大小写 , ^& u- u/ }5 o8 x$ o% w
用法: int strncmpi(char *str1, char *str2, unsigned maxlen); : [) Y1 y0 M* _3 E# J
程序例: 
% E3 {& C6 T. l* {#include <STRING.H>; y0 c. I0 E0 B& Q2 P
#include <STDIO.H>
, J2 Y9 x; U- h, Cint main(void)
- j0 M6 ]6 u8 y9 g" O: ^, t{ 5 |* V, s5 {3 \( k5 @* l
char *buf1 = "BBB", *buf2 = "bbb";
2 I3 c; h6 C$ e) fint ptr; 3 `. g* H9 X7 h+ T+ s
ptr = strcmpi(buf2, buf1); 
4 A, B7 u& L) }: L8 a$ vif (ptr > 0)
* `' l: k0 p! e3 Z Q& e5 J+ @printf("buffer 2 is greater than buffer 1\n"); - K" Y! u W' P. N3 v! S3 ?1 V
if (ptr < 0) ! g8 u/ A$ f- i
printf("buffer 2 is less than buffer 1\n"); 1 K+ ]! N( h/ [4 W1 d
if (ptr == 0) . X" x6 i& y9 u9 E( D
printf("buffer 2 equals buffer 1\n"); 
0 Y3 d( r. p0 C& Ireturn 0; 2 Y' l0 D9 L' G! J
}
) C( g: T" o' ^' @3 R9 w
" B* ^4 ]1 E2 Z% I4 T5 m2 Z9 T6 |5 ~( o# j' Q3 o9 {; ?/ t

+ ?/ T/ k4 v/ q+ C6 D* b5 J函数名: strcpy & a3 n: M0 z# h+ c* A& o e
功能: 串拷贝
0 I2 v4 q9 N* {" k( _- v/ |- _1 ~用法: char *strcpy(char *str1, char *str2); 9 J; M3 |5 h Z/ C
程序例: 
3 v3 u S& v2 N1 D#include <STDIO.H>% B! i- V0 f& N! W% ~! S+ \
#include <STRING.H>
 [! m7 G7 _4 Zint main(void)
% u- W0 s. Y1 H9 |: }5 p2 W/ X{
. C0 ]* i% ^9 U5 X! Y& schar string[10]; / D. P/ M* G3 n3 |4 r- i2 |
char *str1 = "abcdefghi"; ; k, q" c) x' P
strcpy(string, str1); 3 k" u/ ^% N$ J* O
printf("%s\n", string); E2 T1 u7 J' q! ], [ b8 A2 C, [
return 0;
, }2 A5 e2 ^2 h! @: F$ P7 t}
7 v# ^: l0 | _4 _# A2 d. D- o2 q3 v* K b. C7 l/ k3 A

' s6 t+ F/ j, u$ R) i! ]7 Q! i( ~5 d: Y+ b
函数名: strcspn 
' n) f: F5 ~# G# M! K0 S功能: 在串中查找第一个给定字符集内容的段 . o# l0 U" s$ h$ h$ b$ G# @$ c
用法: int strcspn(char *str1, char *str2);
: B/ ]7 m0 o( ^% S( r! W3 r程序例: 
9 W( x- G; _# o5 J4 V3 u+ r& T#include <STDIO.H>* |' \- `+ d5 I9 J7 _
#include <STRING.H>; `/ z9 ?4 h3 X- |8 j
#include <ALLOC.H>" F4 E6 t, v/ N( I& z7 H [* V r2 L) [
int main(void) 4 t3 i# a, l/ a0 O( E
{ : G& [9 J ]( }* n- w2 [
char *string1 = "1234567890"; 2 {5 w r$ Y1 G$ }. z
char *string2 = "747DC8";
7 R% U/ A4 Q+ [1 e* rint length; 
' W& p3 I; h) _length = strcspn(string1, string2);
% k7 I$ O, P8 g6 F) i. \" f* Sprintf("Character where strings intersect is at position %d\n", length); - ~+ s/ {! ?, W% K3 A. ]5 K
return 0; 5 F9 j! P9 ?# K8 g- Z
} ; j+ b$ z+ J; h* b, Q

! ~/ m/ L' J' ?; I) ?7 n' [. X+ @% @
& ~1 n/ i3 F z! K9 ~2 p2 j, Z
函数名: strdup % P! v/ @: {4 ?4 W& }$ N
功能: 将串拷贝到新建的位置处 ! h6 G' U5 e/ U% J) {! W
用法: char *strdup(char *str); % H9 C- G* h! M9 }5 ^- [. \! w
程序例: 
2 f1 I, A' B' L+ S; h: w; p#include <STDIO.H>* T0 L' O+ r9 A0 P0 P9 B& d0 ~
#include <STRING.H>
' U6 z7 l- k! s6 {9 v1 a#include <ALLOC.H>
6 i* U' a5 V [0 b& aint main(void)
" W7 f, k+ Q9 C0 x{
8 w8 _5 b" e$ H: ]7 tchar *dup_str, *string = "abcde"; 
) U; e: G7 K+ E% R' z3 b( Ddup_str = strdup(string);
( f; W/ ]! O* {printf("%s\n", dup_str);
1 Q" }# r7 Z9 X( Y6 Wfree(dup_str); 
" L j! v0 E) breturn 0; & r5 t% Z- B% Q q4 G
}
3 s, I- s8 [# _% G" @* r; H" {: d' n1 A' ^9 H
0 X3 @2 b6 E' U& }( B

& H# B7 x4 c. d: I. n函数名: stricmp 
2 z6 ^ u) U- a功能: 以大小写不敏感方式比较两个串 ' C) }- K( |3 I* X2 l# I' S& w! [! v
用法: int stricmp(char *str1, char *str2);
0 w @, Y6 S" d程序例: 
3 W K% x1 }. a3 u* d0 @6 r#include <STRING.H>- U- ^: {3 e( M! @
#include <STDIO.H> [) o' G. Q! J* u
int main(void) + U) t, T1 ~0 x
{ ! }/ q U! n1 M8 r$ C
char *buf1 = "BBB", *buf2 = "bbb";
, `; z" g' K( {# m8 P( j5 |5 p; Rint ptr; 
4 v: E1 D9 z8 X9 s& c7 d, Q* Aptr = stricmp(buf2, buf1); 
! L" Z# u( Z$ J# M1 u( X8 d; wif (ptr > 0)
, o: n8 S% r( {3 G9 M& n1 B/ a7 bprintf("buffer 2 is greater than buffer 1\n"); 
4 O: Z6 R! p, e- Oif (ptr < 0) + }- ~4 U7 X4 s7 [1 I# O' I
printf("buffer 2 is less than buffer 1\n"); 
; q1 g+ H( R5 _, U `if (ptr == 0) & c% K. ?% c, G) d3 m* { h
printf("buffer 2 equals buffer 1\n"); 3 P- S* D6 |: ~0 }) M5 e
return 0;
9 o" m: R1 Z, B! ~6 e} . k8 { g* q: V4 I" j
3 r0 l1 d1 D! ?* _
& k" t" {# ^. C* h( X
函数名: strerror 
1 R3 x6 \6 j6 ?" n% M9 d! }功能: 返回指向错误信息字符串的指针
( h: i7 b f# w: u用法: char *strerror(int errnum);
8 |' d$ o0 E8 |* F* k# l# M程序例: 
& i; y1 t% o3 }# M, o [" o8 q#include <STDIO.H>0 X" e. u4 [1 e
#include <ERRNO.H>, q# G. R. l& d! ]
int main(void) * d" Z+ ] u* A$ E2 n
{
1 F9 }" p! Z4 A1 p) l5 mchar *buffer; 5 }2 H; \: P7 f x
buffer = strerror(errno); 8 f, L* b& J0 z' S; m' x2 C
printf("Error: %s\n", buffer); / P- h3 x/ }& r8 Q. S% @& K
return 0; 9 n0 J/ X$ _$ g; J
} v3 `8 X2 N; z2 s- e: M3 p
1 K+ J9 h3 u$ |
 W* w5 O( L* x: F2 e, n8 P

& b1 P V+ w6 V, o" q& S% _% E) A函数名: strcmpi 2 P! S" y; h# O3 ~' ^+ u1 B1 i7 S: C
功能: 将一个串与另一个比较, 不管大小写 + ]8 s$ ?* L$ c/ D1 i8 F, C% m% e
用法: int strcmpi(char *str1, char *str2); ^; _, o4 b# w3 `# f
程序例: - N, K/ C/ [& v {* q
#include <STRING.H>( X: w& w, Y3 x; R# ?( f
#include <STDIO.H>$ M+ u2 O3 R2 e5 V1 ?3 P
int main(void)
+ q/ P. h) _- P* L* d( j{
5 T: D6 [/ ~" s1 `$ achar *buf1 = "BBB", *buf2 = "bbb"; # K+ V+ {4 k0 E% v# V
int ptr; 7 N9 h x. `# v5 ]% n- ~
ptr = strcmpi(buf2, buf1); + e* Z% a% Q. B! t; h R. |
if (ptr > 0) ! Y- A/ y3 j9 i8 K [/ u! H
printf("buffer 2 is greater than buffer 1\n"); 8 Y9 i7 D$ `( L+ j& g8 |4 N
if (ptr < 0) 7 k! f2 d0 H& q7 ]( s- A& q8 I
printf("buffer 2 is less than buffer 1\n"); " p4 F) H/ i& \2 U( f1 Q2 {* f
if (ptr == 0) 0 h6 ? d2 ?) S9 ]: c4 ~/ [0 G
printf("buffer 2 equals buffer 1\n"); ; ]1 Q$ y# _# p8 o
return 0;
' H5 ^8 x1 T5 h5 w4 H/ L7 ?} , Q4 A9 Q. N1 w/ s' R( o& V

7 ?% f* F* h9 q, ]% W, q G) U; E. ^5 \

7 I. o7 l0 C& v+ `" ^+ W1 L) l, d: c/ R函数名: strncmp 
) ?& x2 w! x# R: W8 u, @; N( `, r- I功能: 串比较
) ]6 _' j' y: |: y$ q0 Y, Y用法: int strncmp(char *str1, char *str2, int maxlen); " B4 U3 x9 e( M# k- J
程序例: 
: X$ H4 J X$ ^% U- j9 A5 S#include <STRING.H>2 @% u; x: V2 {8 e$ |' _
#include <STDIO.H>5 E# W$ l3 e$ A u) n
int main(void) 
+ H6 T' z* y" L% I9 |5 O{
* a, \+ s5 W! m) u5 K; s- \- u1 z' {char *buf1 = "aaabbb", *buf2 = "bbbccc", *buf3 = "ccc"; ! Y% J4 H8 k% ]$ w
int ptr; 
$ i. u0 z( Y; } s; a0 O. r7 pptr = strncmp(buf2,buf1,3);
' J) ^+ j& Y1 @' E" oif (ptr > 0)
4 t Z) n( U) u+ {! _, v/ h) Sprintf("buffer 2 is greater than buffer 1\n");
" Q8 z9 e: y* celse
/ x( D+ u/ ~; b# x9 z- Q6 cprintf("buffer 2 is less than buffer 1\n"); 
9 g* M! g: Q. @1 F. j: eptr = strncmp(buf2,buf3,3); 6 v5 ]- f+ x& h
if (ptr > 0)
( [! s3 [% E9 n1 j9 Gprintf("buffer 2 is greater than buffer 3\n"); 2 M% N# {) _4 k* w7 k7 R
else 5 l7 {" Y- M7 l/ L
printf("buffer 2 is less than buffer 3\n"); 
: w! p3 [! h' q" h* Z6 kreturn(0); ) g# Z6 @+ v& Z9 a& c
}
! m% P1 Z0 k. U" C! h0 Q# @+ @( w/ t5 @ i
1 h: O% N$ }; J- z1 m+ [ w
函数名: strncmpi % p; o8 v4 I8 {% N
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" _9 w( i( t' e用法: int strncmpi(char *str1, char *str2); ; |( n; ~: r# i& U7 d R
程序例: & {& o x4 Q) ?) [" g1 U
#include <STRING.H>
4 H. d; R( D1 q& d# e# h4 u#include <STDIO.H>
" d+ `3 x, |' L2 H1 n9 Uint main(void)
+ x7 X! v q9 {# z{ . e! p; Q6 O! I1 ~' c- @
char *buf1 = "BBBccc", *buf2 = "bbbccc"; $ e2 {' \' I5 O, a I
int ptr; 
4 u1 N' _! y/ Q ?" s- G3 tptr = strncmpi(buf2,buf1,3); 
. h6 D# i6 `: M: ] G# G# j( Oif (ptr > 0)
8 V0 W o. T) h7 |! Vprintf("buffer 2 is greater than buffer 1\n"); 
9 D( d: v! e' S3 M8 C* aif (ptr < 0)
9 U% D7 O2 e2 F, q' [printf("buffer 2 is less than buffer 1\n"); 
& v" X) `# E& T4 x, O+ a. F5 k7 p- Eif (ptr == 0) ' `" Z/ r& W6 `8 o/ c
printf("buffer 2 equals buffer 1\n"); 
- \/ ^0 E) j$ `- v2 greturn 0; 
2 ?/ D3 P% H7 v6 K W- I}
( J2 j: l K/ H+ A
# G+ ~& r, c& q9 d( Y0 W B4 n- U& E7 O# y1 @1 ^
函数名: strncpy 
. s8 I: g! f7 ~% o功能: 串拷贝
% L8 n7 `, n' J+ N' T用法: char *strncpy(char *destin, char *source, int maxlen);
- v2 c- d# @, u5 T程序例: 
9 h$ B' v7 e: Y; G0 i+ V- F8 |#include <STDIO.H>
8 }6 N/ k0 {9 p) |#include <STRING.H>: f, _' ~& o( z: W3 O' _
int main(void) ! T+ W$ m) ]7 c- p. B' J
{
0 N8 u: Z1 _+ P( \# Y' |char string[10];
* m1 l% a3 M) X/ ]+ {1 g6 Pchar *str1 = "abcdefghi"; 
3 t O3 k& S9 v7 A( ~& }strncpy(string, str1, 3); & o" l7 w0 g' T$ d" g3 w
string[3] = '\0'; ' K: r! s8 G$ Z" T7 Z8 ?/ X) ^
printf("%s\n", string);
' {7 b+ d1 i" X: Z x9 Ireturn 0; 2 C9 H0 e b# t1 n6 K7 \ L
} 2 R" Y; `' L+ @7 }! F

# z& F+ l5 H. U3 f$ e
9 C- d8 s& r( V8 i9 Y" O函数名: strnicmp 
- V' n! y3 s) C* E4 Q功能: 不注重大小写地比较两个串
& C. @, H, ?1 D0 ]- k" O& q用法: int strnicmp(char *str1, char *str2, unsigned maxlen); 4 n+ N, m2 H0 ]
程序例: 
* k! i6 e. M) A: P+ c6 s' J% y$ C#include <STRING.H>
0 ]2 ]% z* Y: l* I' f#include <STDIO.H>
4 I% g' [# Z( p8 B& Wint main(void) q1 |3 o; K. {/ i
{
# h. Z! X+ s- f& M% P4 I+ c" }char *buf1 = "BBBccc", *buf2 = "bbbccc"; & U* d R. W% ~ `
int ptr; ! g3 z$ Y/ w& |5 S2 x
ptr = strnicmp(buf2, buf1, 3); 
. o: j& O. n. Q/ o% ]if (ptr > 0)
! E* N- Z2 {# P+ bprintf("buffer 2 is greater than buffer 1\n"); 
2 ^8 }" y7 r$ c, g; S3 lif (ptr < 0) 0 g0 Z5 \5 `6 _$ _2 q) q; |
printf("buffer 2 is less than buffer 1\n"); 
8 N6 ?& r% t& P [, h' dif (ptr == 0)
( U9 i# o/ A, ]& s ]5 ?printf("buffer 2 equals buffer 1\n"); % V: }5 l& @2 d/ m- O
return 0; / G9 H5 @% \" ?: L' R6 i8 E( G
} 7 ] r4 ]. e. i
& J. q8 H1 R, F' T u

! A- K3 q: [. }. ]( C+ Z$ B1 h
/ f6 U, p, }/ K& `. |函数名: strnset 
, Y. U3 J* ?* z/ y; E8 o. M功能: 将一个串中的所有字符都设为指定字符 & |" }8 X2 ^ i8 H3 H# ]- v' a
用法: char *strnset(char *str, char ch, unsigned n);
( W! x' L/ u8 k* S u4 r程序例: 
: n+ T9 n7 V: Y* h3 S#include <STDIO.H>
. ?: w7 q& @# f4 h4 {% |8 [6 q#include <STRING.H>) ?8 j0 U9 o; A
int main(void)
2 B4 V: b, t- E$ M# ^: h{ : [3 w. Y t4 E' P0 i; c+ j
char *string = "abcdefghijklmnopqrstuvwxyz"; + T" G# a- P" p3 R; I3 S
char letter = 'x'; 
; q% l6 x8 w% a3 w1 \printf("string before strnset: %s\n", string); 9 m! K. F! j% v+ n3 P# Q8 j
strnset(string, letter, 13);
# s4 j, _8 n2 cprintf("string after strnset: %s\n", string); 
0 j, A# V! N* i2 E0 Vreturn 0;
- C! k$ p5 T! v1 Q% A} - ~: P( @- Q: u( X1 z
1 i' O/ m, J; d6 h! h4 u+ [0 z

( F: Z1 c2 X, H7 T7 g0 d( ~! u函数名: strpbrk 
( X }7 v# K4 }# S功能: 在串中查找给定字符集中的字符
" b8 c; a! E9 \用法: char *strpbrk(char *str1, char *str2); 3 H. \, u! d+ ~8 v
程序例: 
8 D k" K- c6 C6 N#include <STDIO.H>
" a4 t" u; y+ `9 a#include <STRING.H>
2 L9 M g$ a% h: Z1 Q1 J" h5 R( iint main(void)
- a" B" d/ F: I- H{
7 z# J6 p" S! H; t3 achar *string1 = "abcdefghijklmnopqrstuvwxyz"; 9 v) g" N' x1 e
char *string2 = "onm";
+ c- g/ |; n0 Kchar *ptr; ' ]1 n4 P M) L7 j: `
ptr = strpbrk(string1, string2); 2 J: P& i' f/ g" |- R7 E. U' J
if (ptr)
+ E4 P. ^7 o4 G3 `printf("strpbrk found first character: %c\n", *ptr); ' s: D. s$ x& m/ }4 h0 D
else . p) w C3 R* H; Q5 P
printf("strpbrk didn't find character in set\n"); 
. W% G7 X5 i( e0 Areturn 0; % N* g4 h1 o+ B: x- U3 o
}
3 W1 a, e+ Y/ w: r/ Y+ W8 H
; j* v7 o' a7 H- c' v/ _) F$ @
, H, t5 S. @5 r, }1 V( |2 I
函数名: strrchr 
$ q! t9 M( \: C7 L; f功能: 在串中查找指定字符的最后一个出现 ! ~2 A" } G1 q$ P" ?$ K
用法: char *strrchr(char *str, char c); ' _- J* j4 D ^1 U
程序例: 2 j8 ~$ z2 G$ o* i, B6 Z0 j/ {% `
#include <STRING.H>
. i* C! ]/ `5 d8 y4 V7 R1 n1 C#include <STDIO.H>, F! T) R; A, {3 K9 e2 Y8 {
int main(void) ' `0 b X$ F& Y" T( E0 t& q
{ / H# e8 e8 j1 @
char string[15];
) o2 U M) ^6 G5 g7 ~3 I4 @char *ptr, c = 'r'; 
0 [8 S& |/ n% h& Vstrcpy(string, "This is a string"); : ~2 [3 Z4 j/ ^) B6 w
ptr = strrchr(string, c); : _. y9 b s% `9 y6 ]
if (ptr)
2 p5 N9 y& t. J: ]7 G# E: K& l# @printf("The character %c is at position: %d\n", c, ptr-string); " T y% r) x. x& M9 \6 ?$ ~, u2 m
else 4 ^/ L6 t# R- r! ]9 N4 r
printf("The character was not found\n");
1 {. n1 g' `- N0 ]& Rreturn 0;
6 `& Q. W! L6 {} 
2 W3 p. u2 G' G3 ~- A4 o' D& u+ i! {

9 ]$ {7 B2 u7 u3 q3 T8 b( L+ D4 o; C7 ]1 A9 H+ U
函数名: strrev 
- ?5 t9 [# t* z/ R( I8 g功能: 串倒转 " w; C, _4 E4 z
用法: char *strrev(char *str);
9 C" @' N# D: e' U, j程序例: 
- K" I: N: _2 P- E8 D#include <STRING.H>" ?+ C* E9 F' C, O# K
#include <STDIO.H>4 M0 ?# i& |- S v' y( x
int main(void) 8 q. i F& @# H" d9 F
{
5 m1 }' [$ f; b# c* y' Jchar *forward = "string"; ) D, w: b+ Y5 y Z( J
printf("Before strrev(): %s\n", forward);
, T' M S( D$ b% V+ A }strrev(forward);
' k0 V+ ^$ M1 ?$ ~# N7 |2 S6 {9 Uprintf("After strrev(): %s\n", forward);
! B, A; _3 a! ]0 n, u$ r N( @return 0;
( f4 T, D; E" A3 Y y0 M} 
4 X* T. r* p- N" j5 x( z
- H4 G5 U1 z; ~+ U' R+ b- F函数名: strset - a8 L" c. t# v2 g. T+ F$ S: ?2 ?6 o
功能: 将一个串中的所有字符都设为指定字符
8 P' N9 s( a! v0 h! @用法: char *strset(char *str, char c);
3 | C% Z( T5 y: D" a程序例: 
6 q) D o. E8 @#include <STDIO.H>- S: c; H/ p3 }; B# n4 T0 H; w7 E
#include <STRING.H>
+ P% Q7 ^7 v& Nint main(void) ( C- V2 R* |: H3 C2 X( l2 R* b
{
$ J' w9 j8 M4 K' X) vchar string[10] = "123456789";
" l+ V; a9 v3 o* ~% |( K8 \: E9 Gchar symbol = 'c'; 
: ~& g n+ b+ K, t- m0 Q+ \% Sprintf("Before strset(): %s\n", string); 8 t% b& y' {- n
strset(string, symbol);
- N6 l; `6 L g& T1 k# ^" xprintf("After strset(): %s\n", string); $ b# f( [: U: `
return 0;
& f( B% M9 w1 s; ]9 d}
" k ? N& [9 ^, P: v, x1 p* j
5 b) H, b' @. x3 `1 E
$ D* _% t" v% z9 Q1 J$ v" s6 ?4 x9 g$ o, [. x4 T( ~$ W* g
函数名: strspn 8 L+ r+ n, w/ W4 w" t$ x
功能: 在串中查找指定字符集的子集的第一次出现 , P$ u; t/ |' g9 [( {% e4 t
用法: int strspn(char *str1, char *str2); ! J8 _* V3 t/ Z, v# t4 \+ u8 q
程序例: 
2 E4 W+ F9 n8 T9 v) C0 @0 c6 k S#include <STDIO.H>; T5 g1 V/ h0 ?; p2 H" J& G
#include <STRING.H>
 C5 n0 b/ V8 e8 ~0 k3 E#include <ALLOC.H>
8 t& _ [$ a x, uint main(void) " u0 V a% w) w6 x) f! _& Y( B( d
{
& [0 g1 e1 B- b( c6 W- N9 o* bchar *string1 = "1234567890";
% h& U: d4 [ Pchar *string2 = "123DC8"; # I* V2 _! g) _" D* K6 u1 r
int length; 
2 H* z5 `5 G7 i2 I$ [$ }, C6 Rlength = strspn(string1, string2); . f$ S" g4 x2 g, f }
printf("Character where strings differ is at position %d\n", length);
! X# V' u; {0 }* _& greturn 0; 2 A( z) w0 [' ^/ y% z& \1 F8 w1 N! J
} 2 w& M ^3 ?5 d$ Z
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& B i9 h3 ]% f. h8 i% E; Z函数名: strstr 
- a0 _; m. M( G# Z* P* a功能: 在串中查找指定字符串的第一次出现 5 g- N1 j I' C; e [; ]
用法: char *strstr(char *str1, char *str2);
. U7 m. ~& F. h" i程序例: . O+ b! }- {% T7 v; ?' e- f
#include <STDIO.H>; h' k& B! b% b u2 H7 d5 z. |2 b
#include <STRING.H>6 J5 h) T3 l6 a7 B
int main(void)
5 T( C. K. g k' e. `, _0 {% b{ , j0 ^! Q4 s, ~" ^- Z8 w% r3 T
char *str1 = "Borland International", *str2 = "nation", *ptr; ( o* F5 H% {2 }7 w7 G3 C
ptr = strstr(str1, str2);
1 K7 r. Y. E4 i0 u5 {printf("The substring is: %s\n", ptr); % D) g9 n( C4 J* R
return 0;
7 u: {4 Y' T+ W} 
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函数名: strtod 
# `+ {1 A' v; O- D" @% D6 C功能: 将字符串转换为double型值
* u: O L1 v1 L1 F用法: double strtod(char *str, char **endptr);
8 `1 c2 q5 d5 L4 w: I( @) M程序例: 4 S5 f( T& U. ]( X
#include <STDIO.H>
' A4 Q. g/ P w#include <STDLIB.H>5 e- H& t, ]/ C `
int main(void) 8 [ u# ?8 b' P5 Q3 j
{ * ~( ^, {" n4 S; _1 E% h# ?$ r; O
char input[80], *endptr; 6 p" ]6 j' ~" v
double value; 3 x" M7 n1 E7 l8 f) Q" o- q9 J/ ~, I0 H
printf("Enter a floating point number:"); % t, F. _4 _# H" z! ~) ^ j
gets(input);
" d6 M o9 M; h- W" g; S8 v% Wvalue = strtod(input, &endptr); 7 S1 h! z5 z1 {; o- c* I% K7 K
printf("The string is %s the number is %lf\n", input, value); ! k' M4 `# C' k, O$ G
return 0;
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# O1 _( c, ?: [) K函数名: strtok , k5 L" _; F8 k0 u
功能: 查找由在第二个串中指定的分界符分隔开的单词 ! e, Q+ y U: u7 s e
用法: char *strtok(char *str1, char *str2);
; i& G- S+ ?% @( F程序例: 
, J! ^& b* T9 {8 @7 ]; H/ [; z#include <STRING.H>
& X2 K7 v. b5 M. j$ ?7 W ?#include <STDIO.H>$ `% N6 `- n# b& j
int main(void) ; z# u5 x9 _- {9 d/ p/ i
{
7 g! k2 d6 ^+ z- V7 [1 Nchar input[16] = "abc,d"; : V6 R! H4 D# j0 C
char *p; 
1 R6 F6 d8 F& U/* strtok places a NULL terminator
% G0 ~. k* M# |( D; Oin front of the token, if found */
8 x$ Z) [1 f( H$ [p = strtok(input, ","); ! X" x3 |4 b; J! Z+ X( d+ A9 T
if (p) printf("%s\n", p); 4 q( _* Y5 E0 ]2 j7 b+ a
/* A second call to strtok using a NULL ; b9 e5 G: t- X% M) B1 `
as the first parameter returns a pointer
3 v# {- z1 K+ s& Cto the character following the token */ 8 t8 n$ X- N& Y
p = strtok(NULL, ",");
$ z# {: _. @2 h( F4 Kif (p) printf("%s\n", p);
2 Z) \. J! Z6 Qreturn 0; ' J* Z: G o4 S( a
}
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+ g2 a- I9 M# d; S2 l% k6 y- |# u
函数名: strtol ( G: w! h7 o% U3 c
功能: 将串转换为长整数
* |. z, X2 P+ R4 o用法: long strtol(char *str, char **endptr, int base); 9 t, ~0 \( V8 e" s9 O q
程序例: 
+ Q3 Q4 I% T3 ?#include <STDLIB.H>
5 L0 F: ?! I, ~% B2 \#include <STDIO.H>7 o3 e, K8 ]9 ?+ b. _
int main(void)
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char *string = "87654321", *endptr;
1 c4 i: F# k# P8 L; mlong lnumber; . M# ?; w/ U- T8 R! m0 J
/* strtol converts string to long integer */ " o+ k4 ~! D' ~' i' Z- A2 I+ o# W
lnumber = strtol(string, &endptr, 10);
$ O9 [7 J- i2 i4 U4 u& jprintf("string = %s long = %ld\n", string, lnumber); , o/ z0 s4 p3 V, j( {3 }5 W! \7 y
return 0; - g* V+ J v) t" s& Z2 M" ^
} 
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函数名: strupr , R5 |3 @8 Z8 o$ Y
功能: 将串中的小写字母转换为大写字母 5 b- b& B" M& I l* N% W
用法: char *strupr(char *str); n' B4 U; U4 w
程序例: 
8 x! A9 X. u9 B. }# y, H# z" Y#include <STDIO.H>
- X; i9 y* t4 n& ^#include <STRING.H>4 i' |) d& P8 s% `: I! s( W
int main(void)
' G& {% ]; M& Y: K$ F{
 E( M7 ^8 v, g" @char *string = "abcdefghijklmnopqrstuvwxyz", *ptr; 6 |1 X' _- b( P* W. J
/* converts string to upper case characters */
, [* n4 P8 c b. ~ptr = strupr(string); 3 |% j* w* F9 n' k: p# s/ y) Q
printf("%s\n", ptr);
$ G% h6 Z: l& qreturn 0;
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函数名: swab ' Q5 o9 Q+ A3 z$ C0 d! t$ _2 H4 y
功能: 交换字节
5 @ v- v o* T- _ u s用法: void swab (char *from, char *to, int nbytes); 2 k: x) e( M( o) V9 C
程序例: 
( z% H2 O: o1 F6 |" A5 Y#include <STDLIB.H>
* V& a7 l: b, {$ F4 `! r6 Z% m#include <STDIO.H>9 J+ B) r: v2 N+ D" z
#include <STRING.H>
7 x; M) G8 b U, R, I4 schar source[15] = "rFna koBlrna d"; # K# G) A, W# a, U2 m! G+ V
char target[15]; 
6 ^: N9 k3 L' D) @& B, Vint main(void)
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swab(source, target, strlen(source));
% m0 T) t( q, W( A) Z$ G- C) V- Nprintf("This is target: %s\n", target);
9 q4 R$ g. {7 V D, d/ X8 s3 jreturn 0; 7 ^, ?, }- ~8 L( i7 r/ u
}
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: T8 V- x: g, U/ Z! _' p, ?
函数名: system 
# j% o1 R5 _0 ?* M& o0 x6 B功能: 发出一个DOS命令 9 O! ^7 v" S: X( l; d
用法: int system(char *command); 2 Y5 M- @) V6 N5 H
程序例: 
7 m( k% s( K* E$ o* H2 x) n/ \( i#include <STDLIB.H>2 X2 P, D. K+ E
#include <STDIO.H>
' M* ?3 V8 D5 H+ ]/ cint main(void) $ T& M" n& {* E8 g
{ 4 m& q, c; r* O
printf("About to spawn command.com and run a DOS command\n");
, e5 z+ y8 f6 ?! Csystem("dir"); 2 w5 J. a3 v2 X% C
return 0; ; w, H. [) ^" S3 \
}