数学建模社区-数学中国

标题: 函数大全(s开头) [打印本页]

作者: 韩冰 时间: 2004-10-4 02:55
标题: 函数大全(s开头)
<

>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); 8 S( ^ w- z$ B/ A9 i2 z4 V
/* display the gray scale */ S0 G* l) j; P' `
ht = getmaxy() / 16; ; B) J. U6 k7 u1 N9 Y$ C
xmax = getmaxx();
* ^ h6 F- e3 u" J, ^- `0 U- ty = 0;
9 r1 B0 v$ ~, V, I& l5 L) b Gfor (i=0; i<PAL.SIZE; {
: B) E9 v5 Z$ L$ G/ w2 xsetfillstyle(SOLID_FILL, i);
$ b: }9 m, K2 D; E% G& T8 d4 Ebar(0, y, xmax, y+ht);
* u" U3 M# d7 m8 iy += ht;
2 }/ }8 U- Y, T2 B} 
: {, g+ y% M. E1 @- `! {/* clean up */
- ^7 B6 J* o2 C# i$ T" pgetch();
- n/ ?2 M2 U! N a6 [4 w! k' \closegraph(); , M# e( W, b O. d# E( Y6 c9 D
return 0; % A2 W( G) x" \' n7 H
}
& B, z; @. C$ G: z2 R
2 p+ F" U2 `9 A' J2 z" ?+ @9 Y3 q# H. y; ?" }: D! X
4 L8 g* l5 N8 m
函数名: settextjustify 
' J3 ^+ ]4 S/ i4 `功能: 为图形函数设置文本的对齐方式 * [ p& r* \( G
用法: void far settextjustify(int horiz, int vert); ; T% I( o, B, u" ^1 T
程序例: 
$ T( K7 [2 S/ ^$ `- D9 K U: y( J#include <GRAPHICS.H>
0 }4 f# A1 j6 {& Z+ W#include <STDLIB.H>& N4 U% S! M+ J$ H) I8 m
#include <STDIO.H>6 \4 d" Y0 N' i: D# q
#include <CONIO.H>; p+ S4 i3 ?) h/ O) [8 \, N% d: k( M7 }
/* function prototype */
7 J* M, [, B- h2 R0 n) g2 F8 K0 nvoid xat(int x, int y); 5 b) _; `/ \6 ?3 H* p/ P
/* horizontal text justification settings */
! F/ P8 L* s4 n% i' bchar *hjust[] = { "LEFT_TEXT", ! h+ h8 u* c! `9 t1 R
"CENTER_TEXT", 6 v7 q# c2 l* W+ H. z( {6 U
"RIGHT_TEXT" & x4 J9 L0 h( t/ s
}; : C* H+ e! o) ?' C) ?% d
/* vertical text justification settings */ * e1 _# K# ]0 o$ `# t
char *vjust[] = { "LEFT_TEXT", 9 A6 g( a% a$ r: d7 f& p0 r
"CENTER_TEXT",
0 ?! m# l3 ^1 j0 s( Y' V. ^9 L9 V. V"RIGHT_TEXT" 8 S3 }6 N* n+ v. m0 `
}; 
7 {$ @" Z- W% _0 c) B' ]! Cint main(void)
) [* ~1 ?* c; G N5 Z{ - m0 o- K, V3 j }8 }/ h
/* request auto detection */ 8 j H3 j8 k* ^9 e8 [1 M2 W
int gdriver = DETECT, gmode, errorcode;
. b9 f, v( A4 p& L, d8 `, G' p* kint midx, midy, hj, vj; " L n- B: l3 v9 N# Y8 Z1 o
char msg[80]; : m! R' q) ?% h$ r
/* initialize graphics and local variables */ : V2 g: A- i' |8 O$ [5 q1 N0 H7 u
initgraph(&gdriver, &gmode, ""); 
0 q9 F7 w4 ^/ t; p6 @/* read result of initialization */ + D& L9 t4 G* J2 N
errorcode = graphresult();
1 K. l0 V- S4 d5 O- R2 N2 { oif (errorcode != grOk) /* an error occurred */ # B# z# m; `2 s3 Z
{ t8 ?0 v1 o7 Y, S) H* n5 `
printf("Graphics error: %s\n", grapherrormsg(errorcode)); # X8 M5 ~8 `! s! |* J2 _% b6 g
printf("Press any key to halt:");
8 A! m, i: b% D! vgetch();
0 x/ ~5 m+ v1 {+ U1 L/ W4 Fexit(1); /* terminate with an error code */
# j1 o7 l- {1 m} 
( |0 y/ T3 w1 x# I9 i1 ]midx = getmaxx() / 2;
, L6 Q+ X% ]0 H. B& Z6 Mmidy = getmaxy() / 2; 
) k G# V9 t8 @( ^- Z$ E$ m/* loop through text justifications */ ) `' O& T9 A& j- j- r
for (hj=LEFT_TEXT; hj<=RIGHT_TEXT; hj++) 3 d8 k4 {8 m; }- a( Z2 ~* e) p
for (vj=LEFT_TEXT; vj<=RIGHT_TEXT; vj++) " {# h4 ~( x& v( c4 Z6 A
{ $ [0 y5 u5 w" c& W
cleardevice();
: f5 s% @- A* M5 b+ _, `/* set the text justification */
$ h5 i7 p/ v' {) Vsettextjustify(hj, vj); . p$ |$ k1 g$ z5 v/ q* X
/* create a message string */
8 B. |( R. i9 b( Zsprintf(msg, "%s %s", hjust[hj], vjust[vj]); 3 s; y* @! ~# n) ~
/* create cross hairs on the screen */ 7 |% v) a" j' Y( L$ W
xat(midx, midy); 
* c0 N$ w) n, f" P) y( l/* output the message */
9 |5 Z. z+ I5 Houttextxy(midx, midy, msg); - y8 E4 @3 }1 z' @! v: s
getch(); / p- m+ o/ O% V8 Q' J
} 
2 X' Y n, ^2 v8 r8 p/* clean up */ ' P- H5 e. P5 m: Z
closegraph();
% V8 c. S M; S6 c5 @# Zreturn 0;
8 [" D! j4 i, |8 D3 F} ' a6 Y, B# g- _* j0 R
/* draw an "x" at (x, y) */
' K( a& e5 ], ]: Z1 }void xat(int x, int y)
; q, {" G0 Y. {: v{ 8 n8 A4 w5 U) d* z) `
line(x-4, y, x+4, y);
& ~6 g) p% x4 l( }' z3 g, Wline(x, y-4, x, y+4); 3 O0 ~. A5 @7 }0 Z; x
} 
' y& @( y8 b$ r7 ~' z1 V4 D- X. E7 Z0 Z$ D; u: ^- S4 {
5 z6 s# w8 \; Y& U6 X) p
函数名: settextstyle 6 t, h2 A+ i2 V
功能: 为图形输出设置当前的文本属性 5 `% {) |* n; j7 a6 m
用法: void far settextstyle (int font, int direction, char size); ; I* T/ }7 v' P" V" B
程序例: ; ?/ R0 |3 B& y5 e6 Z" ~$ @
#include <GRAPHICS.H>$ ]2 M. J! ?' ^: T
#include <STDLIB.H>
+ w$ x$ v6 U8 D" h$ F8 g#include <STDIO.H>
' D5 R/ P" y' C( T9 p#include <CONIO.H>) n! q! i6 c0 d2 d
/* the names of the text styles supported */
, t) g6 p' |4 w8 E* ^char *fname[] = { "DEFAULT font", ( y" G# D o. R" L1 s+ c, X
"TRIPLEX font", : j. W$ @1 k W* F3 T1 o4 ]
"SMALL font",
9 R, d9 @" h3 b U" N. H"SANS SERIF font", - x6 L# j: U p M7 `$ |
"GOTHIC font"
; c6 m# E4 l; v" _6 E2 `}; 
 p- c0 l2 K# Y' ]& B+ G$ a3 S9 wint main(void) 6 j9 K0 G7 Z- ?1 m
{
7 O# x* w0 O2 }% R9 M/* request auto detection */
+ J' V) o- [" |, z0 W: R7 y9 vint gdriver = DETECT, gmode, errorcode;
int style, midx, midy;
: c; B4 J" Y' {) M* Qint size = 1; 
4 G8 F! [6 W; O4 a z; r7 U/* initialize graphics and local variables */
, p5 X5 v+ p H, |. G1 G, j% E5 E6 hinitgraph(&gdriver, &gmode, ""); 5 J F+ V$ U: P$ J- M
/* read result of initialization */
' k2 o1 d* [( P7 berrorcode = graphresult();
4 B+ w2 Q- K4 o5 N7 y. f( q2 Hif (errorcode != grOk) /* an error occurred */ 6 }! }* S7 t/ {! ?# R0 O9 b" V
{
! }$ F$ o. s" w! G/ B$ pprintf("Graphics error: %s\n", grapherrormsg(errorcode));
7 g! T) M; _% s4 i3 s6 `printf("Press any key to halt:"); * U& S7 A r4 u9 l; Y
getch(); % Z; m t! k# i4 H) T& D
exit(1); /* terminate with an error code */
0 M7 ?$ A! R1 C3 q* q} 
8 y: }' P9 ~0 o1 K6 M u; T4 qmidx = getmaxx() / 2; * H* q% x' w5 c2 \4 {$ B
midy = getmaxy() / 2; 
/ W) H* {/ x8 w8 zsettextjustify(CENTER_TEXT, CENTER_TEXT); & l! o3 i; i& E1 i3 n8 q
/* loop through the available text styles */
9 g4 c: E1 e3 t# ^9 R9 _for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) ; ~2 g# E+ Q3 U9 I$ n% }2 D
{ ( M) s# p) |! T& e0 Q$ ?
cleardevice();
3 T( Q- U, B; v$ k( r% bif (style == TRIPLEX_FONT)
 u* q- P# Y3 V& G0 N0 f1 @size = 4; 
" `9 X' x2 m( p4 p/* select the text style */
/ f8 Z* Y6 N: o0 Y' \9 _+ ^/ |7 bsettextstyle(style, HORIZ_DIR, size); , C5 v! m: ?8 o" \+ x+ t6 U7 l
/* output a message */ ! o0 y$ x# o: `
outtextxy(midx, midy, fname[style]);
, J- r: W' b* P* W9 L9 j. ^! Rgetch(); 9 e1 {; s4 k( P% D4 S+ _+ H
} 
& U$ c4 K& [& T r! Z! W* r/* clean up */ 9 Z5 z; M# T& D# a( C2 r0 u& P
closegraph();
! N8 P4 G/ A9 H# G* Oreturn 0;
- Z& Y5 k/ K0 o+ M. I3 V}
& `$ f5 w, k; ?8 Q
: V0 p0 h* w5 ]' \# v$ N$ |
1 h9 z, O: u" \ L4 ^函数名: settextstyle k& h" k3 l( E% E
功能: 为图形输出设置当前的文本属性
: |3 I( {( D, j2 P$ _1 M. @用法: void far settextstyle (int font, int direction, char size);
* p, H6 I; K/ E3 t& e. s5 [程序例: 
" c* V3 i9 X {: E3 ]#include <GRAPHICS.H>
# T! V/ x+ {' X+ r2 S2 m#include <STDLIB.H>* W, h& l, k1 F$ u# s* J4 F
#include <STDIO.H>
; {* A4 t, P9 E2 b; r$ ^#include <CONIO.H> N3 t9 j7 V$ U) i8 G$ J& _
/* the names of the text styles supported */ 0 g0 T/ P. U Q* L
char *fname[] = { "DEFAULT font",
4 K. ~# P: T/ S& L+ b) E! L"TRIPLEX font", 1 V6 q( L! `* m) B
"SMALL font",
( x: a- k& x4 W"SANS SERIF font", 0 a3 q5 W. _# k7 n/ m, `; o
"GOTHIC font"
& K3 _: @1 R5 z}; + Y4 j. }& F+ S' R
int main(void) . _# X% ~7 f1 _$ _! }1 ^
{
- X" y6 M) ~% ~ K, ?/* request auto detection */
. a0 [) n: _% v8 c6 `int gdriver = DETECT, gmode, errorcode; . ^' m! }& \$ T$ H3 M
int style, midx, midy;
7 R! U5 D+ h6 H$ rint size = 1; # n d* Y& }1 K- e6 }8 h; R) ^: x' v
/* initialize graphics and local variables */
# B- p5 r! ]( s& d2 M8 yinitgraph(&gdriver, &gmode, ""); + J6 I1 M9 q" e y3 R7 i% ~
/* read result of initialization */
9 a1 B2 O6 W8 ]2 t8 @errorcode = graphresult();
9 g$ \/ X# x* y2 |& _8 o+ gif (errorcode != grOk) /* an error occurred */
; e; u2 p0 U4 {" D4 b# \1 t{
9 `, c1 ^( u8 C0 kprintf("Graphics error: %s\n", grapherrormsg(errorcode)); ' B+ M; C. }9 d/ k* ]! t$ v
printf("Press any key to halt:");
5 ~! c6 X& K8 j' w& Dgetch(); 4 @2 J- ^% A0 e4 F; @
exit(1); /* terminate with an error code */ ! U/ k. z* t/ Z! i4 m
} / h) R/ A- p' R( V
midx = getmaxx() / 2;
7 [% p! b1 v! R3 U& Emidy = getmaxy() / 2; 
% {" C# {& u7 |( Dsettextjustify(CENTER_TEXT, CENTER_TEXT); / z# w& p1 b* O* [
/* loop through the available text styles */ 3 A; d1 Q. w9 m! J( e2 Y
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) 0 D! Q) L$ W# h3 D: Z4 y. F- n
{ ) O5 N# |) K, }2 F( i0 n
cleardevice(); 2 N B& e" U# s5 O: r0 e: ^
if (style == TRIPLEX_FONT) 6 t5 e. z" Q( o* w4 v D+ G
size = 4; 8 s$ Q& h. P) b% t; Q( c
/* select the text style */
- Q6 ^# P- Z0 v6 H' ]settextstyle(style, HORIZ_DIR, size); 
# c" g: E' A" Z7 I& \6 k7 w/* output a message */ ) S# n& e! x! `- S6 O8 H
outtextxy(midx, midy, fname[style]); 2 [( V, v, K u$ T( o" x) V/ h
getch(); " a8 e5 Z7 f2 v
} 6 R( m W# B8 F f+ b" r) B8 X
/* clean up */ # b' {8 E( K/ L2 B) E; G
closegraph();
! v! ]. I' P2 ~2 T8 j1 h& Kreturn 0; 8 |6 Y2 }+ k4 b8 V5 o# K, V6 |
} 6 a6 i- t E. |, G! V3 w
! h' e- x) S4 G9 w# w

( p7 r( n$ r% U; h0 ]0 D3 ~+ y2 I6 d5 N函数名: settime 
& f0 H# W+ p7 A' a% ?7 H功能: 设置系统时间
; d( R) ^, _3 v8 W7 s用法: void settime(struct time *timep);
* R7 \1 o- k! o程序例: $ i* W( L2 b6 s& a4 c* R
#include <STDIO.H>: H8 B. z" g+ R, R, m
#include <DOS.H>
int main(void)
& Z" n: O! K7 k# Y- Z9 d7 h& ]{
) e4 C& l# [: c0 x/ ?" gstruct time t; 
3 r/ u+ t% o! m9 U$ {9 F. y# q1 Kgettime(&t);
# |/ {& o9 \6 O! a# pprintf("The current minute is: %d\n", t.ti_min);
+ _# f4 D% Z7 n+ D; q( e T! sprintf("The current hour is: %d\n", t.ti_hour); $ j+ w J$ N1 m% Z6 U3 Y
printf("The current hundredth of a second is: %d\n", t.ti_hund);
5 j. V, }5 m( G+ p+ _" m* e6 Y. D% Mprintf("The current second is: %d\n", t.ti_sec); 
5 I T1 C$ A% b$ Y w1 s/* Add one to the minutes struct element and then call settime */
8 V3 S4 w# J2 J7 h4 U0 Ft.ti_min++;
; g& w; ^) b* @9 z+ q! xsettime(&t); ! l4 |. |+ s3 g$ S: I9 G
return 0;
0 r }& S- l' N7 D! v1 d9 _2 j} 9 B& F6 g- h, T' x: b9 u7 @3 }: E

: d% L' P; ^, B t+ n& X& y3 T F- G# `& b' f) x$ a7 G+ [
函数名: setusercharsize 
0 j+ x+ w3 c# ]功能: 为矢量字体改变字符宽度和高度
" M8 M. L0 g7 a+ A. @用法: void far setusercharsize(int multx, int dirx, int multy, int diry);
0 k( V1 B7 N- V: p! n4 P& O程序例: 
& Y- v0 L0 H' ?$ a5 `#include <GRAPHICS.H>
$ G0 R. t6 P# I#include <STDLIB.H>6 U, V! q9 g% Q6 J4 ~
#include <STDIO.H>
- o5 B6 m( A3 N#include <CONIO.H>
/ }$ v6 o: I0 Kint main(void) - s' J$ U2 M# e' A$ L
{ + b4 O# D: ~% D& w `5 ]
/* request autodetection */
! I3 w6 T3 x( j% w0 o5 Aint gdriver = DETECT, gmode, errorcode; 
! o) P4 K- Q9 }( x2 Y/* initialize graphics and local variables */ + s2 b+ P8 `+ ]/ t9 i
initgraph(&gdriver, &gmode, ""); 
0 @: o- H6 _9 Y( y5 g& J/ [/* read result of initialization */
5 h0 x8 h' v) e2 `, a1 p8 j+ derrorcode = graphresult(); - p. h8 M/ n7 a# E1 U1 B- E
if (errorcode != grOk) /* an error occurred */
$ x$ J8 J: V* Y7 ]& c3 z{ + M4 ]( X' r* O* }
printf("Graphics error: %s\n", grapherrormsg(errorcode));
+ @$ R' C2 S; b- v4 v9 G, kprintf("Press any key to halt:");
, Y/ l3 B' @+ n( a" c* ogetch();
" D: d' }# Y/ @0 O% oexit(1); /* terminate with an error code */ ( N7 X- q! l N5 [
} 
4 ~0 O7 b- [* s$ W0 n1 e/* select a text style */ + z$ M0 v9 D" i4 Q: w) L
settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4); 
( @8 Q1 h1 `8 d9 |8 t( x/* move to the text starting position */
! T$ I, M: w' o( l3 ?moveto(0, getmaxy() / 2); b/ d& n4 z4 `2 f- H
/* output some normal text */ 5 z* z$ j6 _+ L4 b
outtext("Norm "); 
0 R0 j1 C: o0 j& f* F" n( q/* make the text 1/3 the normal width */ 1 |- D; T/ d( v5 h5 y
setusercharsize(1, 3, 1, 1); 9 P0 I/ l9 v9 p5 A v
outtext("Short "); 7 H: V! E1 S4 v; Y6 y
/* make the text 3 times normal width */ 0 B! b% }' H, q( u) y( G& _) C
setusercharsize(3, 1, 1, 1);
1 P, P) A; f' `; {9 B# vouttext("Wide"); 
& E! h- B( X4 N6 y0 y1 n4 a' A/* clean up */
+ n" o2 V- J. e0 c# ?; U6 e% m( Igetch();
) X2 N' n+ R& D9 z3 H8 Rclosegraph();
0 c/ J2 Y' ]( ^$ e" xreturn 0; 3 `% v+ _/ o9 Y9 ]1 y" [
} 7 ?7 V) R; Q2 s( S

 Z) h2 W$ j+ g+ Z函数名: setvbuf 
- d: R$ I% m8 |- j- p5 `功能: 把缓冲区与流相关
; c' o" s6 W e+ ^3 }3 D$ C用法: int setvbuf(FILE *stream, char *buf, int type, unsigned size); % Q1 q) w/ q+ o* {1 q; b
程序例: : S0 H: c: D; @( J3 w! a6 ^
#include <STDIO.H>
% ]: o; m. ]/ l$ v5 K8 D3 kint main(void)
/ g% I. D8 h' S( o{
0 [5 w0 Q1 z$ E1 r* \7 @FILE *input, *output;
* X' c- \- ~+ F% q2 fchar bufr[512]; 
9 z8 {. _5 e. Q6 tinput = fopen("file.in", "r+b");
% ^- l) k# y& h* f; Q9 }output = fopen("file.out", "w"); " }( P6 A# `; y& g3 F
/* set up input stream for minimal disk access,
) ?) }6 T) z/ p* Zusing our own character buffer */
3 J0 q0 m* g$ ?- uif (setvbuf(input, bufr, _IOFBF, 512) != 0)
# m9 E% G. t6 b7 z$ [printf("failed to set up buffer for input file\n"); 0 k8 _! ]9 c/ U) E) [& J! p7 L
else 8 ?+ x( \' |, K9 Y
printf("buffer set up for input file\n"); 
, [; M. C0 v- g/* set up output stream for line buffering using space that ' {- c: s( ^" Y: \
will be obtained through an indirect call to malloc */
+ ] k' x V b; O5 ]0 Q, Kif (setvbuf(output, NULL, _IOLBF, 132) != 0) , p; e& B1 a2 C% O2 J; ]6 U
printf("failed to set up buffer for output file\n");
. ^. H5 h, n0 n1 yelse
" ?9 r/ `4 k. C& l2 T$ [6 Oprintf("buffer set up for output file\n"); 
" Q, S5 {, E8 O7 n) E9 T/* perform file I/O here */ 3 {& k- E4 a% {$ E/ |+ R
/* close files */ $ }' B5 E# y* Q, a' ^- s2 p
fclose(input);
1 G! V3 I; V9 H, Y- vfclose(output);
& B, ?& C% s$ Y! R G. e# vreturn 0;
3 t) ]4 w* S6 T) o2 o} / s* t, |& C5 P1 y- `" T5 n9 m

# I1 c3 N+ I( d$ S& k2 m% t! S* H" d( x

1 d, I" E# a) i3 {0 |函数名: setvect 
7 n. `$ Y, s0 U. e功能: 设置中断矢量入口 + r. E& b; `- ~7 b
用法: void setvect(int intr_num, void interrupt(*isr)()); + ~% ^4 l# X- |8 O/ S% ]1 f; c
程序例: # k6 o6 P1 b8 M$ X' E
/***NOTE:
$ e4 V/ ?, j/ \2 J ^9 O- m+ X% EThis is an interrupt service routine. You can NOT compile this
9 y! Y1 `; Y s) ?4 @& u' O1 j/ x* cprogram with Test Stack Overflow turned on and get an executable $ G- F7 s' F/ K8 Q5 k* u* k
file which will operate correctly. */ 
8 T# Z8 _* K6 L#include <STDIO.H>
$ I G5 e6 z C9 \8 \; [#include <DOS.H>2 l" m' K/ A! u
#include <CONIO.H>8 r! f5 @8 g1 B; e- F" U6 C9 O
#define INTR 0X1C /* The clock tick interrupt */ # F, o' \3 f" }+ ?
void interrupt ( *oldhandler)(void); * x p% h& t3 G k0 J
int count=0; 0 r+ m% d2 a. W( ~" ^, ?
void interrupt handler(void)
; W4 t* o+ {2 [{ 1 [8 K# T, ~/ L4 ^
/* increase the global counter */ 2 a( x: S. {0 T+ U: D2 b
count++; $ A9 f$ @( m6 u$ A; Q0 c
/* call the old routine */ ! i2 q( N; s5 L; r1 n5 V, J( v
oldhandler(); ! `1 n7 Y. }1 W! q5 G- y
} 
 r* a4 g) u; o4 t$ V4 q; J/ yint main(void) 7 |% @* S) y8 ]( x* v3 E
{
. x& j6 \; y! f6 ^% |/* save the old interrupt vector */ 6 v4 V ?2 X- b Q$ I: Z
oldhandler = getvect(INTR); ; O0 Z5 B4 f* q+ V+ q( I
/* install the new interrupt handler */
& W" i8 O( x1 u: nsetvect(INTR, handler); 
, z0 `' f6 t/ h1 e( s/* loop until the counter exceeds 20 */
% U3 x. {. w# w( l+ Vwhile (count < 20)
( E$ S* x1 `) oprintf("count is %d\n",count); 
7 R3 E) U$ O1 Y2 ~5 C# l$ P0 t. \/* reset the old interrupt handler */ . y5 S' _1 z# O# f% t; ]9 ]
setvect(INTR, oldhandler); 
+ `4 i% D4 h4 a% treturn 0; ' m* E. c1 }( ?" b- M& K
} * W( @/ d7 Y# m

" S8 L) F2 A4 X9 y/ Y, g1 x3 t+ P$ x, g
函数名: setverify 4 ]: X3 i$ Q" y# h+ n' z& ^
功能: 设置验证状态
' x& k0 X: Q% J" l" Y+ s: d用法: void setverify(int value); 7 b0 o, Q2 P5 I( x' h/ T
程序例: + [( F- {! H5 F% I. |1 e, t& Y# r
#include <STDIO.H>2 ]1 I6 a: p8 A* K3 z
#include <CONIO.H>6 E; W' A5 K3 k ?% z
#include <DOS.H>
1 P0 x& k: B) a" U* z( B. ^int main(void) ! k/ ]- H% m" |/ c5 V' s$ {1 g; t
{ . r: t: M2 l& m$ z. k( u
int verify_flag; 4 v. B3 Z! |; N# y! v* a7 {
printf("Enter 0 to set verify flag off\n"); & q: v$ y" M- |9 [
printf("Enter 1 to set verify flag on\n"); + W3 R* P+ S4 E& G& F" Y% F- n
verify_flag = getch() - 0; + a/ m* ?' Y: l5 D( d' H, W4 [) G4 S
setverify(verify_flag); ; I4 V; t% \6 e# T0 Q1 }; T
if (getverify()) 7 K" b1 }$ O" z0 h2 ?3 ], t1 S' [
printf("DOS verify flag is on\n");
5 @6 E7 w" S; d( P- C- xelse
5 b" g8 @: A3 D6 \/ E8 \: @printf("DOS verify flag is off\n"); 
# m1 h2 k) p$ P# ureturn 0;
( J+ k/ y1 [ W+ H; I) B}
$ p/ T5 P1 |/ r. D" |5 f; ]( s7 F! _ B) R5 U% U
& t9 C# L* y# r `, @
函数名: setviewport 
3 G2 Q" Q; f. Q! E# G功能: 为图形输出设置当前视口 # s; z& O; p3 h# V3 d: y
用法: void far setviewport(int left, int top, int right,
& F9 |& r) J, d( P' F7 b1 ^' pint bottom, int clipflag); ! `- h4 _" g7 S: u/ _0 E1 s
程序例: " b8 S1 E1 M, }
#include <GRAPHICS.H>
1 p! b( O9 M# \- ]9 d& O+ d' [$ N#include <STDLIB.H># J5 b; z& g7 k0 P; {( [( Q; u" O+ m
#include <STDIO.H>7 U2 I3 B, [: E
#include <CONIO.H>
$ R. j- i5 d% [* S+ w# ]. E' Y#define CLIP_ON 1 /* activates clipping in viewport */ 
+ j7 n% S' k6 O, p9 q4 S8 O7 |4 B( Oint main(void)
; C& u- G, k; G5 V4 S! w. Y2 O{ 6 p) P" p7 ]7 c" Y
/* request auto detection */ # Q$ f9 \/ S# c
int gdriver = DETECT, gmode, errorcode; 
; z( T. P" q' E8 O: {5 @/* initialize graphics and local variables */
( B4 Z& ]- s, w3 z, n) iinitgraph(&gdriver, &gmode, ""); 
3 I2 Z# r. G2 B2 N/* read result of initialization */
' b+ }3 e3 w5 ?5 S: l% P; Werrorcode = graphresult(); 9 `2 E9 t$ j: S- I! q( E4 \, @
if (errorcode != grOk) /* an error occurred */
0 G: E: j5 Q# ^{ 4 U' s- b1 `( i2 f
printf("Graphics error: %s\n", grapherrormsg(errorcode));
3 J4 c4 }% ?7 _4 D6 q' h/ Kprintf("Press any key to halt:");
: x' A( v3 [: C( Egetch(); / O* ]0 z' q' I$ b: c
exit(1); /* terminate with an error code */
, M4 J$ y) P* }. z/ X6 A} & f& j' G# W, M9 B) @: x
setcolor(getmaxcolor()); 
5 u; P% G# z6 E Q$ B% r/* message in default full-screen viewport */ 8 L- \9 Z. R$ T( D* A0 P% S' o$ U
outtextxy(0, 0, "* <-- (0, 0) in default viewport"); 
, `: E, t- I6 Z1 ?/ q/* create a smaller viewport */
/ ~$ q# o6 h asetviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON); 
% s( W8 A9 t1 @# g# v# ]/* display some text */
6 `$ t# c2 j/ L: A6 q5 j Zouttextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 
9 O1 o$ N/ B# ^, l J I/* clean up */ s) x7 L* p5 I) U, c E
getch();
. W' [, b. X& k$ x6 S7 t& c2 rclosegraph();
8 i( c1 H3 L: e, P3 X8 P4 w* dreturn 0; " O+ `# {' ?' C' q
}
$ A+ M$ ?1 \6 a i3 V( n/ |4 r
5 [2 [: o; ^) _/ C+ ~
# d" A; l9 c- h3 t函数名: setvisualpage " {+ h9 n5 l9 `4 {0 |5 ?
功能: 设置可见图形页号 2 P7 i" B- n8 O! ^9 n
用法: void far setvisualpage(int pagenum);
- b( e- y4 T$ q' O7 i0 M6 l程序例: " |3 K3 @+ Y2 L |+ V
#include <GRAPHICS.H>9 t8 w+ Q o$ k& ]# c
#include <STDLIB.H>. W s6 a- h5 i- V) D: l0 h* }
#include <STDIO.H>
* M) j: \) ~1 j0 j4 P$ r6 l#include <CONIO.H>3 X2 j& G) T% W" f
int main(void)
 a* l: _1 L$ f: R6 k0 g; G. ~{ " M- E$ G5 a8 P0 g* g
/* select a driver and mode that supports */
. S* B3 l7 I; u0 r' D3 ]; O/* multiple pages. */
5 i. |8 N# {& _' sint gdriver = EGA, gmode = EGAHI, errorcode; 2 a+ w9 ]5 R5 W4 S7 [5 H
int x, y, ht; 
6 D! R1 P, \. o: J+ C& D+ ]/* initialize graphics and local variables */ ' }' ^2 M9 t1 C3 q; F4 g) W
initgraph(&gdriver, &gmode, ""); 
: {7 U+ W- q* t C8 d2 S' }4 p/* read result of initialization */ $ ^$ R/ e, q. j" E9 Y+ O3 u' y: z
errorcode = graphresult(); . S" N# J8 i h ?5 [
if (errorcode != grOk) /* an error occurred */ , E6 g0 D( B5 v+ j
{
0 D0 X- c; F0 Gprintf("Graphics error: %s\n", grapherrormsg(errorcode));
! ]$ O! ^! q/ k8 P* M! @* R. y2 g' Vprintf("Press any key to halt:");
6 C% ]2 ]6 z+ y5 h9 Y- ?getch(); 0 F, }5 S" Q; J. I2 t! \) D
exit(1); /* terminate with an error code */
# X" `" x6 c' V9 i+ ^, F5 ^3 I} 
6 v5 e0 |- z6 T* }0 f" h. d3 mx = getmaxx() / 2; / i. O4 f8 I) k& m
y = getmaxy() / 2;
* `. v2 U/ C6 D% w4 b) B8 _1 {ht = textheight("W"); $ W0 t% I5 T( a# g O2 o/ R0 V
/* select the off screen page for drawing */
8 }& A7 x* W+ b+ Y1 usetactivepage(1); 
7 a6 P/ e* Y' m/* draw a line on page #1 */ $ R2 }; b* t3 Q3 e2 u( F* a3 B
line(0, 0, getmaxx(), getmaxy()); # o) Y0 f& f$ m1 g
/* output a message on page #1 */ 7 w. G8 U3 {- l6 G+ [: G4 l1 V; r1 _
settextjustify(CENTER_TEXT, CENTER_TEXT); / i/ r0 a/ O' R/ Y6 B' n
outtextxy(x, y, "This is page #1:");
' e. N0 f$ ~( s5 o8 Routtextxy(x, y+ht, "Press any key to halt:"); & @2 j, |! b( ]" T% h, o+ h
/* select drawing to page #0 */
) a/ E/ o; w3 m N! c5 o: Csetactivepage(0); & u% r, B+ C( j1 N o3 h
/* output a message on page #0 */
* O* K* a7 O/ O! o2 ^# {outtextxy(x, y, "This is page #0."); + s H3 d! g% J& ~+ `- X9 w7 E1 i( c
outtextxy(x, y+ht, "Press any key to view page #1:"); 4 O0 ^/ g& U; o9 ?3 p
getch(); 0 N1 N$ L4 v4 L/ |8 |0 n! j, c
/* select page #1 as the visible page */
1 r i) ~: [+ w) O1 P# |setvisualpage(1); 
8 ?0 K4 f9 O- e/ z0 H) w7 Y/* clean up */ 4 [* ?( E" X/ R
getch(); + u3 i1 s, w5 T* {
closegraph();
% `* j, L8 e: w) Ereturn 0;
9 ]: S; Y: k6 E4 ~} - D, C7 d7 d# b/ G& ~& Y' ?
% u0 J+ ?' ?( X9 `' U

" P) p" `, t5 Z' N' I函数名: setwritemode 
$ U3 Y. o; l% B2 g) C* Y; O功能: 设置图形方式下画线的输出模式
 i" O& r' E8 v$ R1 o6 l用法: void far setwritemode(int mode); , {- M* M8 [5 Z" S; \; ]) f
程序例: 
% k7 `7 k7 Q8 N# N+ {# f#include <GRAPHICS.H>- o1 a8 M$ `& d3 R" z
#include <STDLIB.H>+ b9 J8 D" ~: \6 q
#include <STDIO.H>4 h3 y3 g& _: U% S% w+ H0 ^+ X
#include <CONIO.H>. x0 J/ K% H7 {. {, \4 ~3 u+ A: y0 N
int main() / [) y+ |$ L. t, H
{ 5 o' p/ M% \( z0 J+ f6 ^- C
/* request auto detection */ % h) \" l( r' J& O) F) h& v9 j
int gdriver = DETECT, gmode, errorcode;
+ ^7 }, }+ I% N; I3 q. z% Xint xmax, ymax; 8 }* R, s. N* v1 K2 ]
/* initialize graphics and local variables */
, P8 G- F1 i2 T, oinitgraph(&gdriver, &gmode, ""); ! r# G1 N9 a* { U
/* read result of initialization */ $ H2 K5 @* ]) U& E3 J
errorcode = graphresult();
% U8 F: R8 {9 ~if (errorcode != grOk) /* an error occurred */ 1 N/ i) @2 R$ z# u( k. _; Q
{ * x, @4 O7 a* r$ p1 @/ |4 m z
printf("Graphics error: %s\n", grapherrormsg(errorcode)); 5 b0 C# g. W0 C Z( ^" s2 G! v* x6 p
printf("Press any key to halt:"); 8 ?0 U" G6 G& S; [% U
getch(); ' F4 H# j. e# ]' H) h5 B
exit(1); /* terminate with an error code */ ( ?6 P& e1 \7 Z3 B* b# Y9 f5 ~
} 4 i0 h; C0 [: B4 q. C
xmax = getmaxx();
- O9 m$ o ]2 g# Oymax = getmaxy(); : [" c7 C- c! s
/* select XOR drawing mode */
/ X+ |& Z+ O L8 lsetwritemode(XOR_PUT); 5 K$ z R9 l! p+ k$ Q
/* draw a line */ " ~6 M2 w2 s9 F" N/ Z5 y; n5 r5 ]
line(0, 0, xmax, ymax);
2 b5 S7 R4 u3 Q6 A- t, v5 cgetch(); % z; j7 h6 g: x
/* erase the line by drawing over it */
$ u1 C% t3 { A* p* Eline(0, 0, xmax, ymax);
9 ]! O. i' N( H* qgetch(); 
3 J w' Y% V! \/ \& `/* select overwrite drawing mode */
3 ^: U- D' {- M' g" B' P$ qsetwritemode(COPY_PUT); 
8 C, s' A3 R. Y5 |& k: }; F8 v/* draw a line */
" q' U3 U; l, \- p8 Q4 A1 ?line(0, 0, xmax, ymax); ) O$ j, D3 P. Z
/* clean up */
3 k, ?( ?% E* y& U* p# K9 W) Xgetch();
0 F; p( g& g$ X5 P3 ]0 zclosegraph();
6 a$ D+ }$ M. ]3 C# K( O! z2 Kreturn 0; * Y- }: Q- h& J& f/ |$ E9 h
}
2 Y1 c+ y `9 E, ?& v y
3 G* t0 Z$ n; G+ |& J& A( N/ p
/ v: ?/ @9 u: ?- P* s% [函数名: signal
" } [6 S# v: H- m功能: 设置某一信号的对应动作 $ ]9 z) e& f# c, y
用法: int signal(int sig, sigfun fname);
0 w2 Z; t8 e5 T" D g" y( |程序例: $ S) n4 c6 S2 p$ u5 G8 ^
/* This example installs a signal handler routine for SIGFPE, ( w: h. d5 v' J! S3 X) Z
catches an integer overflow condition, makes an adjustment
, g/ y* |1 e9 o5 p. `% ito AX register, and returns. This example program MAY cause
" b* I0 H" d7 o) }7 H+ z2 D2 ?$ t2 a4 Vyour computer to crash, and will produce runtime errors
" z( f( z: g, [) |3 Wdepending on which memory model is used. 3 q0 c8 ?. y( H: A' i
*/ 
1 J* H0 C o( D5 P( ]$ q#pragma inline
( y) t6 Q! @" y. y( d#include <STDIO.H>. L. K( o' T& A
#include <SIGNAL.H>% ]/ ?4 b2 G0 k* e
void Catcher(int sig, int type, int *reglist) * N" _% v" f! H) s; Z Q
{ & w4 z V1 o% h W6 y! o
printf("Caught it!\n");
6 W$ a& I" c8 n! S5 ?*(reglist + 8) = 3; /* make return AX = 3 */
+ t5 } _# f G; {, O} 
+ e+ x9 [! i, Iint main(void) ( k& U" y! ]" Y8 N% e6 q
{ 9 G/ h- S; H) N: i) c# Q
signal(SIGFPE, Catcher); + H: m q/ p1 D, Q. i* `* \: i
asm mov ax,07FFFH /* AX = 32767 */
. K0 c6 r4 L4 M5 @! Z3 H; wasm inc ax /* cause overflow */
 p9 L4 U$ x1 U9 ]- e1 M( e& Nasm into /* activate handler */ . c# }2 {; h3 ~- j: j, w: [
/* The handler set AX to 3 on return. If that hadn't happened,
# y7 b$ P, I* C' b3 m- Qthere would have been another exception when the next 'into'
, i6 g" y$ P7 Mwas executed after the 'dec' instruction. */
: S0 |# O2 c2 aasm dec ax /* no overflow now */
# K$ F$ i( ]: \# X# Wasm into /* doesn't activate */
6 P! m" `/ `3 F& M' {return 0; , M& `* c4 ?5 d8 I
}
7 V* Y' Z- \$ [6 }; ^8 h' i& J% y+ |- W( @4 D2 i, u% f+ R
/ q- y I' L- k% f

* K# p. p9 q$ R4 g' H ~5 r* N函数名: sin 
; J9 n) {) l3 j+ l功能: 正弦函数
5 g$ w( n, ~& H) K1 E; T用法: double sin(double x); 9 Z# y1 a# o m9 j4 K9 o, M0 a2 ^+ @
程序例: ]6 O# H6 z$ z. }" ~/ _; d
#include <STDIO.H>( r; I% g2 \. ~( }
#include <MATH.H>% q0 ^" i- D- ]* B
int main(void) , O, ?4 ?5 M1 s' I" e% [, Q3 C$ z
{ 7 b! G& D5 o: d" [- ^
double result, x = 0.5; 2 m# G8 X* x8 I
result = sin(x); `6 ?8 B8 T4 g* t$ _
printf("The sin() of %lf is %lf\n", x, result); . u, |9 ?) R) @
return 0;
5 A; E4 A4 v" X& ~! w9 s+ c} ; [% Q5 s, f% y' z h3 e/ }! ]+ N
# C6 D9 P8 A$ m
8 V4 ~) q! @. f ]7 R
函数名: sinh 
' q* D0 y; z$ y0 H& c. K1 _功能: 双曲正弦函数 $ e4 m/ \# _9 Z
用法: double sinh(double x);
7 S1 c2 _% E9 F: A0 i程序例: 6 P# l( p3 G% r0 H" i
#include <STDIO.H>
( H4 w7 }8 y. B5 m- L#include <MATH.H>
; k, l- F9 ]- H1 D$ z& I# Yint main(void)
- `4 O U/ S* [- g: i z1 p{
( H3 ^- m1 h! V' X- Y- G3 v# Qdouble result, x = 0.5; 
- M5 ?6 @9 b: v. Cresult = sinh(x);
! S8 U" R6 i/ B2 X0 ?printf("The hyperbolic sin() of %lf is %lf\n", x, result); 3 d5 {; |6 j/ W I2 [+ P# s
return 0;
$ ~- b, U2 ~1 h! I" z; w) T} , [0 W* t6 I5 a; z( d. p( M

2 c' @# }3 [6 ~ w9 b# `9 R1 s$ H5 X
" n) Q+ H P: |- L
函数名: sleep , x3 G" W! @& x% c k
功能: 执行挂起一段时间
: C, s( k3 W9 m B) f4 D) f用法: unsigned sleep(unsigned seconds);
; O6 t3 F1 Y9 q; \! n) @程序例: ) a3 L3 l0 a4 ] j
#include <DOS.H>; Z$ \ T1 X5 E
#include <STDIO.H>& Q$ ~; O2 w& J _0 p
int main(void)
" q9 y8 h* g" j* @{
3 a1 ` {* ^3 J5 x+ z3 c: @int i; ; a$ p2 f- W- L/ p( B- u% V$ b
for (i=1; i<5; i++)
8 f- A/ ?4 S) i8 ^{ ; e: V8 [( u" }; [
printf("Sleeping for %d seconds\n", i); 1 P7 m- c* b: y7 X$ [
sleep(i); 8 }( v2 l1 }) k/ s4 ^
} & G4 ?; e% P* b @1 l
return 0;
: R6 I+ n' e& d, A' N/ w7 ]} - C3 v) e- N2 w! S7 Q8 A

2 N! M% c! q4 J0 R8 j; q) Z7 }0 u% D2 I8 F
2 X0 ?) |2 M6 ]- f4 R9 c' b/ C
函数名: sopen # t8 u3 i% R8 ?. ]5 `: ]
功能: 打开一共享文件
9 @$ H9 O. x/ ^3 {4 M" T用法: int sopen(char *pathname, int access, int shflag, int permiss); 6 `/ O/ e' Y8 e D3 ]5 G- C
程序例: $ d D2 D4 H' J0 ?' I; V
#include <IO.H>
: B1 l' k$ J+ I#include <FCNTL.H>: C$ J6 a8 Q% j0 t" `
#include <SYS\STAT.H>
$ o, T7 k, l4 m8 B" e) _#include <PROCESS.H>5 a1 e: a4 C5 f* c U
#include <SHARE.H>5 D3 L ^0 @# B- N e. c; N
#include <STDIO.H>/ f4 Y9 i& q0 G2 ^& J. b1 t
int main(void)
: G/ ?. X( ^$ u{ 8 L, Q: ]9 J/ n) R& ]' f
int handle; " F# u' Y/ v' B4 e8 x* R% I, \
int status; 
: i7 g, V+ E1 c w) Mhandle = sopen("c:\\autoexec.bat", O_RDONLY, SH_DENYNO, S_IREAD); 
# [6 O# A! W: f) sif (!handle)
7 d. x2 Q# L+ H, _% D5 ^2 L/ W{
8 D, P" x# a* w% z2 Q$ Sprintf("sopen failed\n");
) e8 h6 x8 V1 \8 lexit(1); N$ F+ s2 W+ H+ ~2 m) _$ `
} 
. V$ J G/ @! m0 @status = access("c:\\autoexec.bat", 6); ; D2 j8 i* f/ ]1 [0 q
if (status == 0) . Y% M' T8 c& P% U, }' V" D3 ^
printf("read/write access allowed\n"); ' j& \3 J9 I. G+ z$ D$ C8 c
else
5 w. W4 d- |4 r- _; e" nprintf("read/write access not allowed\n"); * `8 k' X6 T K% c6 N1 ~2 ]
close(handle); ! O6 I1 P- v5 q0 C. W& {* z
return 0;
. g, a0 S. b# @' ~& O0 F$ @4 m/ z; _}
& m# m5 ]# Q. A" j
( E2 o8 Z2 P+ O$ g) S6 V3 D8 r* u: Z! p" O

4 n6 H. ?0 {: I% Q% |函数名: sound + b3 V. I' g2 n3 T5 z7 h) Q
功能: 以指定频率打开PC扬声器
. _1 R4 b1 f4 m. I8 _% z, J用法: void sound(unsigned frequency); & T5 }& A0 ?( L' D! m W0 ]8 }
程序例: 2 h- e* H: X8 J3 O& ]4 s3 c
/* Emits a 7-Hz tone for 10 seconds.
0 g2 d5 X* \1 }Your PC may not be able to emit a 7-Hz tone. */ # ?) j& D3 x( X! Y/ B5 H( n b8 t
#include <DOS.H>9 ]2 s) J' o# Q4 x6 M1 y
int main(void)
, y; |- T# Y( e F{ 2 Y# t$ Q& u9 L2 v2 U& E, D
sound(7);
1 y; h5 D$ a9 f1 Idelay(10000);
% [1 c4 U3 v v+ y2 A( pnosound();
4 n1 G7 v4 k) Yreturn 0;
- o. R4 z% O. K( D* M} 
- i* D5 F$ P+ z n* ]5 V' r7 { f# ]9 a

' i3 Q: t4 q3 X) M$ w! ?! B
. s( y8 V& `' `2 y函数名: spawnl 
8 [( T& q* }% Y6 _# X功能: 创建并运行子程序 6 [, } t1 e( j G$ w
用法: int spawnl(int mode, char *pathname, char *arg0,
3 ^& h* O9 J% E8 u7 Barg1, ... argn, NULL);
# N6 p7 H: m. q0 \程序例: 
4 Y$ n; q' f6 H6 g. q4 V' s#include <PROCESS.H>
/ C3 J( T9 T' |# l; `& O; N8 _8 C& Y#include <STDIO.H>9 x2 A% e) I+ M$ @' W
#include <CONIO.H>4 E2 }. x' w& T5 |$ u4 s! M' {
int main(void) 3 x6 H; V9 O6 ~& G: ~; Z
{
. H% a" o5 |, u9 q: ~6 y. Oint result; - ?0 h* d# q7 q f( F
clrscr();
- l) c9 g( P( p/ G! x- E) fresult = spawnl(P_WAIT, "tcc.exe", NULL); $ H8 I1 w2 F1 a+ d3 ]
if (result == -1)
; w; e) t2 R: V4 z9 T) W4 j! e" S{
. Z2 G: m) Y) D% N1 a% Mperror("Error from spawnl");
7 {9 X3 Q2 d' U& I% aexit(1);
( o) G7 U0 P1 ?0 x+ A} 9 ~( F/ L6 w* o9 ?, `% }& V
return 0; ) n. A/ }$ w2 ~! Y4 R
} 0 r+ k& [' C: E9 ~5 ~: j
5 B2 L8 {- u- q5 R3 I: n+ W
 U* o: F4 g8 ?" H
函数名: spawnle 
0 e/ n$ L. p- |4 W9 g功能: 创建并运行子程序
4 ^2 o/ U3 V9 O) d3 a, n4 O' l& ~用法: int spawnle(int mode, char *pathname, char *arg0,
" I A/ k {9 j# J! i% m& x2 Darg1,..., argn, NULL); 7 c& F# a1 y& ^! o
程序例: 
 o% K. E8 M' T5 j x/* spawnle() example */ 
- z/ o3 u/ n8 Q4 p: t#include <PROCESS.H>" \1 I/ c% I! V7 u( Q5 C
#include <STDIO.H>7 }- f9 _( r. @$ O D+ F
#include <CONIO.H>
. {9 z* ]" z1 d' I: i% Dint main(void) ' ^' R3 y4 }; e' S t2 P- K
{
6 p- Y" j( g# N9 n8 k6 e0 fint result; 
! A3 h3 ?. @: g8 W/ U) U: j3 wclrscr(); . X% y* J) \" s$ X% X: |) C
result = spawnle(P_WAIT, "tcc.exe", NULL, NULL);
1 q3 D. \) R8 i! p) pif (result == -1) * G) b/ I {- c7 @$ ?
{ ( I1 G/ g" P: k' {0 M+ f5 M
perror("Error from spawnle"); " q, G( D N+ E, O! T* |' v
exit(1); 2 ~6 J& S7 ?) o+ ~
}
- m+ ]0 r% v( X4 ^: Oreturn 0;
/ A7 H t6 F9 E# d0 Y}
: v% u% n& L9 q( N8 f: G* L% J+ J8 X: I0 W5 Z0 C3 \1 f
, o: M2 d' ^6 f* U

1 Q i0 O9 O* w函数名: sprintf 
3 B- i# h* j1 N/ z( P功能: 送格式化输出到字符串中 % d, T+ y r2 o4 X7 N
用法: int sprintf(char *string, char *farmat [,argument,...]);
$ b' X% K; Q8 r; g# l G8 H, k) F) F程序例: 
- X: R* ]+ a. l" l6 x#include <STDIO.H>
0 J6 B/ L @ `#include <MATH.H>
/ \% n) w2 g5 \. S/ v7 I3 R9 tint main(void)
7 r7 ?) n9 f* |/ a$ I( s{
5 L5 A6 G. ]: b; _& q/ z nchar buffer[80]; # q' Q. w+ \: H- j6 X& u; q, |
sprintf(buffer, "An approximation of Pi is %f\n", M_PI);
! O7 h6 E0 S, \9 V& w( S' ^/ D) n/ Dputs(buffer);
" {: K! z+ K; Qreturn 0;
/ U2 e3 _" {6 j) ]} # u; C1 `( L* l) i; H) g. M8 I& L

2 E' |" J$ a, _3 o- p( _
( e1 y; `% G6 m* W g( X函数名: sqrt ! |* p3 C& u; q H
功能: 计算平方根 $ Q( h$ s. v( l& v7 L& L" W
用法: double sqrt(double x);
3 H* `" G" J4 h* b7 k7 |程序例: 
* `! x/ S- @) D: [" Z% D. q3 t$ a#include <MATH.H>( G8 ^7 e& \4 E8 m
#include <STDIO.H>8 z. D( U9 R( O( n' ?
int main(void) - v8 L+ A, W1 i+ X
{
7 A3 B* \' v- z2 H7 P; u ldouble x = 4.0, result; 
# n4 A% ]7 i3 Y( |* s+ oresult = sqrt(x);
4 R! o) V. b: z7 R0 {printf("The square root of %lf is %lf\n", x, result); 1 Y a% d+ h' L$ q
return 0;
, s% s& X5 F, g# y/ m/ Q8 u} ; x: {9 l v9 ? ~( y
# V+ o9 o0 C3 ^" B" K. T7 j( C' V
函数名: srand 6 q+ X$ Y* ]- `8 D q8 J
功能: 初始化随机数发生器
9 f9 `; V/ [1 F# g& [用法: void srand(unsigned seed);
5 h k$ f( v! u& w程序例: 0 s5 Q) R& _$ y E- H, K% g+ ?9 |
#include <STDLIB.H>
/ p. l& ?" Y9 V# }7 g. N2 S- U#include <STDIO.H>
0 p7 k( Q: I, @7 [- A1 q8 E$ h2 e#include <TIME.H>, V: u7 x. ?! Z$ d( r" ^4 T
int main(void)
- y9 V$ R9 Y: Y& w# e* a, X{ & d$ ^/ `0 z9 s# K5 d0 Y
int i; ; u( n+ f3 p4 W! O) r
time_t t; ( @6 B7 b' y9 N8 d, B
srand((unsigned) time(&t));
, C: `9 G/ y. C `printf("Ten random numbers from 0 to 99\n\n"); # x7 k f s2 Z% d
for(i=0; i<10; i++)
4 _% F" O$ H0 i, z! N" Y+ jprintf("%d\n", rand() % 100);
0 w9 X s# y1 {" Q0 preturn 0;
0 @9 |' f% T0 B% o0 J( M4 g3 V}
/ [7 c, a$ n5 l& J; t* f
/ V* v- X* `- C, u
4 m# ?( G3 M6 e d- @函数名: sscanf 
3 B e3 m. U' ^9 n功能: 执行从字符串中的格式化输入
8 W$ A' e- h) Y6 M; C% B! F; [用法: int sscanf(char *string, char *format[,argument,...]); 8 U4 T' M. u8 f# q x6 r
程序例: 
9 d/ q6 W; ~4 n#include <STDIO.H>
/ Q) F- ?) Y1 [+ q. q#include <CONIO.H>
/ q: K. T% P' N6 Qint main(void) 7 @* J* `' g z9 J$ \
{
+ J' H! J, o5 Schar label[20]; 9 {4 H3 p) F5 m. y1 O
char name[20]; ) [$ N! ]9 z5 z( r
int entries = 0; . x4 ]7 }( d( H' o! f; U: @
int loop, age; : ?: {% }& I ?9 s$ K
double salary; 
, K& M' V5 M! P% D0 r7 [struct Entry_struct ) K1 x/ Z- t& Y* ]: ?' m
{
6 x) w9 f& p" t& c( dchar name[20];
# E$ ~" f `% gint age;
, ~0 k M* \- O, ^" `float salary; # Q5 N- d8 f8 J* m) u
} entry[20]; 
- V9 q3 n8 T/ c5 D/* Input a label as a string of characters restricting to 20 characters */ 9 g2 w' S* @ n/ R$ [6 F
printf("\n\nPlease enter a label for the chart: ");
6 }4 q; t/ Q% @- P- F9 |( Gscanf("%20s", label);
8 ~2 G) W2 V, \% s4 ufflush(stdin); /* flush the input stream in case of bad input */ 
+ B! i# K5 C2 I+ x/* Input number of entries as an integer */ 1 Z( L2 c2 j5 L$ n1 I* u
printf("How many entries will there be? (less than 20) "); D, h* d6 F/ R9 Q
scanf("%d", &entries); N3 P% t- @7 t& K* A# [& ~
fflush(stdin); /* flush the input stream in case of bad input */ 
/ Z! i/ s2 s; Q# ^7 { q4 Q' e/* input a name restricting input to only letters upper or lower case */
& f7 s5 X' d i+ ]for (loop=0;loop<ENTRIES;++LOOP)
$ X5 D3 y* {0 A5 w/ h {
& j9 {9 }- M, j v; W, _: M }1 cprintf("Entry %d\n", loop);
; W; s, P& }+ O5 L7 Gprintf(" Name : ");
( }: Z& W0 M3 t9 F. @6 F; _scanf("%[A-Za-z]", entry[loop].name); 1 P3 Y* V4 b2 f3 j
fflush(stdin); /* flush the input stream in case of bad input */ , ]. T6 F* F8 `% S
/* input an age as an integer */ + C0 J) f9 x- S
printf(" Age : "); + N5 Z7 k' n) h. W
scanf("%d", &entry[loop].age);
. {) h: D. q( h3 I0 [ W1 Yfflush(stdin); /* flush the input stream in case of bad input */ 
 p6 R8 T5 E. s1 U; w9 w/* input a salary as a float */ - A/ `( R1 e9 b* g$ K9 ?
printf(" Salary : "); 1 {8 d7 T8 N+ R1 V0 A k
scanf("%f", &entry[loop].salary); 6 [; J' q0 Z9 `! e5 B! n
fflush(stdin); /* flush the input stream in case of bad input */ ; a2 G# ~3 M; c( }8 S H6 b1 t
} 
# S* q4 z* u& L1 L4 \# k8 g/* Input a name, age and salary as a string, integer, and double */
1 I' o) F# e, }, @. j9 l; {; ^printf("\nPlease enter your name, age and salary\n");
 e k7 Q/ G4 ?4 q' _scanf("%20s %d %lf", name, &age, &salary);
/ ?: L+ _ o7 `0 ?" k3 i4 e! F9 m+ @. X! g: S& u) ~
/* Print out the data that was input */ 4 B0 b2 G7 k$ R* `
printf("\n\nTable %s\n",label); $ z. I& A7 F) ]' {) e
printf("Compiled by %s age %d $%15.2lf\n", name, age, salary);
) }+ C+ d& u3 E5 J$ |printf("-----------------------------------------------------\n"); . ?+ F7 n( H. O& e
for (loop=0;loop<ENTRIES;++LOOP)
( F' P0 E+ l& ~# f0 m6 S6 B, O printf("%4d | %-20s | %5d | %15.2lf\n", 1 g7 U# V# y' b+ _9 ?- Q
loop + 1,
8 E1 d; Y* b0 Q+ l5 E% aentry[loop].name,
9 k: M8 F4 _4 ]- B, Uentry[loop].age, ( P$ }' Z' _2 _$ I7 B* G8 G0 R
entry[loop].salary); . l. h+ [, E' @# o6 u: e
printf("-----------------------------------------------------\n");
3 S% K; r; H; k' B: I+ Sreturn 0;
! H/ [2 G% l2 m' L$ \} : e6 b; ]$ q/ a, v2 }
: X; m* @# U! K0 A% N7 @. b8 E

+ q: @5 I R- s函数名: stat 
1 K; w( B/ D6 x; C, r( G功能: 读取打开文件信息 ! Y u6 a0 q H4 j+ \) J
用法: int stat(char *pathname, struct stat *buff); 2 F6 x, `& x* S5 c, T& y6 p
程序例: 1 M1 d _: K8 R, G! Z0 ?1 y6 m
#include <SYS\STAT.H>9 S# \* @; p8 R; L0 X
#include <STDIO.H>7 H6 v- |) G. w
#include <TIME.H>
 m' K5 ^' @" N) L#define FILENAME "TEST.$$$" 
, h, Y6 {9 s0 Yint main(void) . G: D; F5 T. X, d$ Q
{ 1 |# U+ x& v$ l+ ^- ~, H# g' w
struct stat statbuf;
4 k6 u# h$ U. ]9 }FILE *stream; 
8 X( p" {5 Q/ D1 x& T5 d( S/* open a file for update */
7 A! i. I I& N! M* r8 oif ((stream = fopen(FILENAME, "w+")) == NULL) % |. i; i- a: ~5 x/ ^
{ ; P$ o1 U: F& W2 c
fprintf(stderr, "Cannot open output file.\n"); / c1 E( U4 `$ B# ^( x) P" q, ]
return(1);
' W5 q0 v" X) D. t) E% F- s5 m} ) r2 U+ i5 J5 l B. L
/* get information about the file */
% [- Y' Z! j2 }# Xstat(FILENAME, &statbuf); 
( l, h$ [0 s7 N2 D! v! h3 Xfclose(stream); 
' k4 i% _! q9 h; @( d3 B* G/* display the information returned */
. s2 Y9 m1 T" dif (statbuf.st_mode & S_IFCHR) 2 z+ [9 d n, s) |" L1 p# w" \
printf("Handle refers to a device.\n");
! ~$ y) T& f; X( f4 ^if (statbuf.st_mode & S_IFREG)
8 w1 y6 |/ h- c4 o1 ^4 fprintf("Handle refers to an ordinary file.\n"); ) M; `- ]) U4 D0 p4 d3 @
if (statbuf.st_mode & S_IREAD)
3 F: q: E8 S# {; y/ bprintf("User has read permission on file.\n");
# E7 q7 f- [+ W& t+ m$ z" L- E4 U rif (statbuf.st_mode & S_IWRITE)
: t0 V7 r: d. }8 W: bprintf("User has write permission on file.\n"); 0 A/ N7 c# ?2 W0 ~; V
printf("Drive letter of file: %c\n", 'A'+statbuf.st_dev);
6 D5 D, ]0 b, o* `8 Jprintf("Size of file in bytes: %ld\n", statbuf.st_size); 1 f7 x9 }& T! A/ z2 T6 l
printf("Time file last opened: %s\n", ctime(&statbuf.st_ctime)); * k5 @& b) L7 T! I: C* X
return 0;
" W+ W: l8 D( |" L: Y9 c} : i" Z1 k2 T% t- f/ Y) Y
9 z# J% O: p* c, L* ^3 X" L4 t3 q

/ r1 E4 y% X+ D
# Y0 @7 b( O# B3 D函数名: _status87 
% h5 ]0 F n% Z5 L" e! e( L6 O% F功能: 取浮点状态 5 k; A! V2 k* n6 G: ?4 N5 S
用法: unsigned int _status87(void);
4 M W" }8 g& k; C% u程序例: # n7 q# }: }6 U5 r
#include <STDIO.H>9 r- j2 k" }% x' q# h
#include <FLOAT.H>2 b" F: M0 e% X
int main(void) % ?- ?5 n; j% O$ ]
{
- Z$ z( B4 z9 I* i/ bfloat x;
+ u6 J7 h. z- |6 w8 N4 sdouble y = 1.5e-100; 
2 c1 k! N- F1 \/ W# b' y# Aprintf("Status 87 before error: %x\n", _status87()); 
9 U6 y+ B7 M7 U' u% J& ax = y; /* <-- force an error to occur */ * K1 G+ P' v# ^* R9 s( l
y = x; 6 v5 @. e1 L f* v8 R
printf("Status 87 after error : %x\n", _status87());
6 R: a4 ~! x- M! ?0 z+ sreturn 0;
( U: `( n" y' Z}
( Z+ F1 k% X9 M3 P0 W8 K4 p3 b& x
. p# m2 ^4 t/ T( U9 q h. h" Y1 |9 `$ }7 b0 x
函数名: stime 1 V* I, R+ W' |7 {* G
功能: 设置时间
' V5 Y' _2 t6 \" B0 {: F" z用法: int stime(long *tp); 7 A% Y9 D5 L7 E j8 A7 ~* T
程序例: 
. t) n4 d4 p; c8 t#include <STDIO.H>
3 ] v: m3 e5 T3 U#include <TIME.H>
8 R4 \) B. M5 G6 D$ F#include <DOS.H>7 [% Y7 F! d& q. ^% s0 s
int main(void) % s; q6 [/ G8 R, T- N
{ ! i* W- P0 h$ N; _
time_t t; ( \- }3 g/ _2 [
struct tm *area; 
2 T: u6 n/ j) z0 r" Z- Q- V( Bt = time(NULL);
+ Z+ }' D q9 }, O; M+ x l& Jarea = localtime(&t);
 D$ I+ W& H/ ^9 _printf("Number of seconds since 1/1/1970 is: %ld\n", t);
3 E: ?1 c8 H& t2 T' |printf("Local time is: %s", asctime(area)); ; h, d3 l& F# }3 K3 q
t++;
4 f, _8 ]# C: R: z; Y# G: uarea = localtime(&t); 1 x) A; [) @( I; U' l
printf("Add a second: %s", asctime(area)); 9 E D4 ^8 A) A% U
t += 60; 9 a7 i- g9 q- ~7 E. X
area = localtime(&t);
" Y( \+ j! b, m @* C1 {printf("Add a minute: %s", asctime(area)); $ Z- J Z# H5 B) T% o
t += 3600;
3 v5 y" G5 O/ q6 }& B7 p3 iarea = localtime(&t);
; H# _( B) g- N8 r! dprintf("Add an hour: %s", asctime(area)); 
1 f2 g+ l* i. c' f8 T9 N+ \t += 86400L;
& ^" K1 J2 P Z8 N0 Jarea = localtime(&t);
0 \4 M% t2 D4 rprintf("Add a day: %s", asctime(area)); 
+ I1 b4 `2 g9 P, ?: ^t += 2592000L; , \# L( D+ i7 P: f4 D( C
area = localtime(&t); ( b2 }+ U2 ^1 q4 f# N
printf("Add a month: %s", asctime(area)); 
* y; k+ b! ~6 }t += 31536000L; & W9 p, N' E* c! ~" N7 i8 I
area = localtime(&t); ! [/ I4 O# S7 T3 a. w2 M
printf("Add a year: %s", asctime(area)); ; _: }* \4 l5 I- Y9 y5 H( P
return 0;
* K6 g+ e( {, }/ S: Y} 
6 \$ I, h: }- ] D* A- o
1 C7 d; ^" @* ~
" l6 v. d2 F2 W3 n( S" [ [
" l. N$ B3 r/ B2 b9 O函数名: stpcpy 
2 B Z. R5 e F% q5 X3 t# O功能: 拷贝一个字符串到另一个 H$ G0 p$ n4 W
用法: char *stpcpy(char *destin, char *source);
1 Z9 z, R* o7 Q" p; I/ K2 c) G程序例: $ r8 P b' w, }
#include <STDIO.H>& x6 z0 M, a+ C% {
#include <STRING.H>
 c$ T2 c0 q7 Eint main(void)
0 o4 v) m* U. _- B{ l5 `0 o2 I- O, [3 \6 j) M) S6 `0 T
char string[10];
) L$ F3 ]5 U: P: w& M) W$ ~char *str1 = "abcdefghi"; $ p4 E- b; R6 ~
stpcpy(string, str1); / G6 r+ G; P8 X
printf("%s\n", string);
5 l, ^: H; G. p& q! k' y( {. freturn 0;
7 j! j) g |7 A6 ]}
4 K, j x) q1 B @, X/ O9 u3 M! a; K, V+ \1 W

$ Q7 y K4 q* _' m& i# S1 ~
, ?) m$ e% x$ q& p函数名: strcat 
6 Z0 T2 w/ _2 W功能: 字符串拼接函数
. }; E3 a. H8 f- {- y用法: char *strcat(char *destin, char *source);
/ W; U5 e) y/ o& u' z$ A程序例: 
, O1 Q3 H8 [8 N- `#include <STRING.H>
6 j& X. ]2 h1 i9 f#include <STDIO.H>
- T9 N& w2 t. j+ t. R( |int main(void) ! |; Z$ I% i* B2 R2 b1 c
{ % y+ N5 U- \. U% `2 t0 h% e
char destination[25];
, j a: ~" ]0 U1 h( f( W, Xchar *blank = " ", *c = "C++", *Borland = "Borland"; 
4 a' k2 r- b8 vstrcpy(destination, Borland);
5 y" H7 Z" R9 Lstrcat(destination, blank); , C, X4 r: E. Z
strcat(destination, c); 
7 r" c+ i: {* ]% t7 J! Mprintf("%s\n", destination);
# x) ?& d U! t; \return 0; 8 Y: @0 N2 u6 M& f0 G9 B: }8 V
}
: H; g0 v( o0 Q7 \
* E. Y0 |" M* f

7 V9 {/ B( q+ U6 x) z函数名: strchr 
) W. R; W* Y& M9 p/ |2 ^功能: 在一个串中查找给定字符的第一个匹配之处\
$ t y+ n, j6 \( h! S用法: char *strchr(char *str, char c); * [" g% m. q- E. W. N& B% K
程序例: ; V0 ?. k' J+ H/ q: F8 v! g
#include <STRING.H>
% e/ b! S5 x/ ~9 ]. j#include <STDIO.H>( m( h' E! y5 `% ~8 P
int main(void)
6 c) P7 s9 E/ [{ 6 I+ u* n* X- B) s9 e8 `
char string[15];
 A0 ?4 C: B* o( Z0 v4 J- Ychar *ptr, c = 'r'; , ~! T4 M5 R; Q) K) P
strcpy(string, "This is a string"); # `2 `0 `% V5 F8 p( t; t( n6 u* @
ptr = strchr(string, c); ' Q0 S8 H8 j2 y5 a, t* W
if (ptr)
0 k0 F/ d+ X/ ]6 kprintf("The character %c is at position: %d\n", c, ptr-string);
- v; s/ g- Z& Oelse 3 Y, B8 L0 T" m) `
printf("The character was not found\n");
' l _& y1 _4 |) R4 a" s8 P9 hreturn 0;
9 b$ j. m; e4 n/ K4 M8 F' A5 W6 L} ' S R) H+ W1 u" F0 t& P s: j
" O1 U5 ^' H2 G6 i; u
4 |6 l% o! j; N, ^

2 i: ~1 X+ T3 y函数名: strcmp
# _+ }* J# a% O4 m) |8 Y8 P功能: 串比较
7 z: R% c4 z: \( v# n9 B用法: int strcmp(char *str1, char *str2);
9 t; c0 i- W0 D程序例: 
7 h8 b s B% t5 F#include <STRING.H>
; H' n/ i; Z! n. E( Q/ r#include <STDIO.H>
& h! A! F1 a$ u$ b6 m0 k D" Kint main(void)
+ Z. |+ i/ i, o; @6 X{ ; O# f/ i! c2 z" ]
char *buf1 = "aaa", *buf2 = "bbb", *buf3 = "ccc"; % x( m5 G" o. I- q: ~7 D3 n
int ptr; 
' f! }- a; ?8 ]; \ptr = strcmp(buf2, buf1);
6 v4 u! Z8 Q. b1 t( T) o2 `if (ptr > 0)
8 j5 z4 r5 V1 m2 I# s# K0 b$ {8 Hprintf("buffer 2 is greater than buffer 1\n"); ' q, Q, E" {5 E% J/ I) j
else : `+ W# s7 I2 m0 N& T; C
printf("buffer 2 is less than buffer 1\n"); 
; B+ j1 {# m* ?: r/ q' f nptr = strcmp(buf2, buf3);
5 v" G- N9 L+ t& H! X: n% K! w4 Q/ Vif (ptr > 0)
 R8 e: y7 e2 k; g1 K% qprintf("buffer 2 is greater than buffer 3\n"); , s, e+ h$ J7 V! d# N' L
else
! O9 f' p# ~7 iprintf("buffer 2 is less than buffer 3\n"); 
+ r/ O% ^& ?7 z7 a6 g+ D. R, S9 }return 0;
4 O3 A8 M3 X+ l7 M- @' }}
+ W. u' V' P1 \& e# b
6 p- D9 A. \2 U7 W; h: n# {& d. F5 f' q! b7 T2 ]: S
; |9 U- |6 Q3 r W2 Q% b
函数名: strncmpi 
( j/ `( F* }( K9 U$ D功能: 将一个串中的一部分与另一个串比较, 不管大小写 . J" l( ^7 v8 Q N q
用法: int strncmpi(char *str1, char *str2, unsigned maxlen); # h( R$ k9 [8 @" q- O8 z+ Z
程序例: " j7 W5 f+ _0 H5 Z m+ t! K" g
#include <STRING.H>
2 c8 f; d# q- c# q+ j) @6 s#include <STDIO.H>' @+ v/ y1 @/ g6 j1 e) Q
int main(void)
$ q6 |' T+ u. t% g{
( g7 [0 U" H* Dchar *buf1 = "BBB", *buf2 = "bbb";
; P7 O4 Y0 I! Y, Yint ptr; 
+ _& i$ T3 Q& ]1 o; f0 N5 kptr = strcmpi(buf2, buf1); ( ~% Z$ I8 s- I, L+ p2 m
if (ptr > 0) 5 Y. I7 P" ?% a, H
printf("buffer 2 is greater than buffer 1\n"); 
( L% T% y( h0 Mif (ptr < 0)
; A" W" Z y/ r1 U# v- ~1 O1 Mprintf("buffer 2 is less than buffer 1\n"); 
3 X& C' W% y4 g2 y* P! Z- U; }- Q2 V# Lif (ptr == 0) 0 v6 U0 o, m9 y8 B/ x% i1 H7 G
printf("buffer 2 equals buffer 1\n"); Z6 w( z" d {, a* X- E7 A7 r4 [
return 0; % P2 A" Z+ `) i& }& z0 Y( ~( {( X
}
: v0 H* a; X1 m* u' A9 H. q2 f' n1 \2 K: l s* W/ U$ l, a) U

3 V7 p' T7 @8 X5 {6 f2 v f, r( u0 ~
 q g4 F7 \ C1 {+ c函数名: strcpy 
; C r$ x5 B+ z' n功能: 串拷贝 % X) p9 X0 q1 v; u) F5 W$ E
用法: char *strcpy(char *str1, char *str2); . Y, K( X6 `( ^6 s% o( E/ a; l
程序例: , [/ q4 B6 q/ L1 l( q4 z) ]1 H
#include <STDIO.H>
. }- [. W. s! d' q5 R#include <STRING.H>
) t, `/ _: j" L8 F+ |( [/ ^int main(void)
: Q1 a. J, Y/ k7 |7 I7 C{
1 y# a+ U0 B* m% n$ K; a5 xchar string[10]; % i7 W' c; h. Q; D% o5 F7 v/ f" p
char *str1 = "abcdefghi"; 
! B" t! d; v8 \# w) Mstrcpy(string, str1);
& G# A2 x; z4 I9 l/ b6 u" n" Wprintf("%s\n", string);
, C: p2 {* ~; d* T8 f+ Jreturn 0;
* b: ^8 d0 E1 v}
( e! D6 X6 V# `& o { R a2 p5 N' [. J

% u$ U0 p5 v H$ B( `) Z5 s ^# n1 l( u: n: u% J3 G
函数名: strcspn ( ^9 {- D4 D# M( u7 f
功能: 在串中查找第一个给定字符集内容的段 : E k! h) e/ f- b5 m! z
用法: int strcspn(char *str1, char *str2);
6 M8 h) f& C0 H7 k程序例: + J; L5 H5 n+ _3 C
#include <STDIO.H>
# K: h2 ^9 q5 k- f#include <STRING.H>
5 I& G& W6 [1 t" T; K4 E4 Y H#include <ALLOC.H>& h. l' k" x# @8 j+ n6 }
int main(void) & a0 v) I0 z6 D0 `! v( u4 f
{ $ E; ^" f# u- b$ T8 Z
char *string1 = "1234567890"; 1 r. Y: U. o+ l
char *string2 = "747DC8";
6 `9 _, W; {9 U7 Hint length; 
# j3 t. [. T: ^; F/ [2 _) {length = strcspn(string1, string2);
0 G- p% ]0 N4 ^6 |# Q6 N' y. }# ~printf("Character where strings intersect is at position %d\n", length); 
% s$ N9 u0 P, b) A9 E" J* h( g! a1 }return 0;
+ U2 j! Y$ M9 O} & G7 W. ]/ k3 S: O
/ K/ L/ g! K9 c" P2 L6 ~8 o% y
) G2 W* C& V8 c, e9 W3 q

- L3 q9 X8 s( v. ~/ t! e函数名: strdup ( y9 i6 y. \7 Y, {- Z
功能: 将串拷贝到新建的位置处 3 V/ i; p# w- X' d# G- T8 J" R6 c) x
用法: char *strdup(char *str); : k% M' E9 ?9 x) a! ?$ r8 ]
程序例: 9 O3 N& M/ Q# f& E$ ^2 W- J
#include <STDIO.H>1 T: T4 [) f) m
#include <STRING.H>
( a! }- O: Y* k; j3 s" s#include <ALLOC.H>
: |- g/ e y6 y; v% s$ oint main(void)
% {9 o8 f6 L2 ?{
( j: b9 F; Y- cchar *dup_str, *string = "abcde"; 
5 D5 Q$ t! |$ w% K% y" Y5 Bdup_str = strdup(string);
) Y' x' |1 U/ }0 K, W0 |5 h9 L+ Oprintf("%s\n", dup_str); 9 H, e, m: t- u/ r, l7 ?& d) ~; J' p
free(dup_str); 
' \/ q, d: C! Z1 k3 w, M; Y Sreturn 0; 3 A+ x T: y" D
} 4 w8 R8 v% F; W9 [: n

" f h( v _$ H1 l$ }/ c, k. i
5 z' c; w9 B, S/ M& ^+ j$ c: i, b; y1 M- ^
函数名: stricmp : [8 I8 I3 b6 Q( h
功能: 以大小写不敏感方式比较两个串 3 Q% A! @% b3 J& x, B+ g! ^ L
用法: int stricmp(char *str1, char *str2); ' r9 O: N! @) G- U0 H0 m2 F) \
程序例: 8 J" n# G! O# K* p( D
#include <STRING.H>
! h$ f& K0 O: Z- y+ X$ j#include <STDIO.H>
- \9 g6 m2 ?4 e# p/ sint main(void)
 c$ w o, Z( v/ o) U* _2 m{ / B# _: e B/ Q3 F4 x0 @
char *buf1 = "BBB", *buf2 = "bbb";
. C; X0 ~8 _% D8 C6 }int ptr; 
; z# }2 L- s1 x8 r- Mptr = stricmp(buf2, buf1); 
) B0 I1 ?: ?6 i8 oif (ptr > 0)
3 X/ n$ m: ]7 b* P1 pprintf("buffer 2 is greater than buffer 1\n"); 
# w4 M& m) v1 d9 j/ V! m9 ^, Z, Xif (ptr < 0)
: x( j% E% Q' C6 ~& ^( hprintf("buffer 2 is less than buffer 1\n"); 
3 }9 R# X: [/ h) J' fif (ptr == 0) , a1 @8 a3 I8 x" I9 y, h+ ?( e
printf("buffer 2 equals buffer 1\n"); 
" Y7 I- e. m7 D3 ^+ N' ]5 Dreturn 0; ! P' ^8 K; v4 |# W7 v8 @) ]
}
, F, d4 u5 ^) @/ P d' Q8 t; R/ r8 Q" Y/ Y
6 v4 w8 H1 q) W% L1 L
函数名: strerror 3 m% R0 b K5 b6 y8 {& O
功能: 返回指向错误信息字符串的指针
- e: K* {0 w- d/ P- ~0 c5 {% B用法: char *strerror(int errnum); 1 Z p5 h w) l1 A
程序例: 5 @ _. J, w) I: q9 D
#include <STDIO.H>4 i8 a+ |! L4 I6 g% L& E
#include <ERRNO.H>
) s1 I- M6 y3 q6 E' B P! F1 C7 Vint main(void) & D; A! E6 Z0 z( E) V9 P
{
6 Q8 y: C- K/ \' c7 Jchar *buffer;
( D4 M$ f4 B9 R! ]4 zbuffer = strerror(errno); ! n( N) J: I1 s. E. B
printf("Error: %s\n", buffer);
/ \2 P; E2 F5 J- S4 _' Rreturn 0; / _2 l7 `6 i! b9 X y
} 0 f$ G5 D3 U$ W0 M

, o) _1 _/ z X* ?1 A
0 L1 C* Y) {: k2 L* i5 `4 g- I0 s( E, s/ J
函数名: strcmpi ' l8 R& ^8 S, W1 _! L
功能: 将一个串与另一个比较, 不管大小写
0 u0 |% j; F! |1 X+ ? k2 T* K用法: int strcmpi(char *str1, char *str2); 8 x( |1 t$ w, V( {/ Z
程序例: 3 @) U8 z' |& b, o0 h# y
#include <STRING.H>
- c }4 X3 e# X* r8 S! b#include <STDIO.H>
( G4 v1 ?3 j% v6 C/ I5 S9 F9 Tint main(void) ! z1 U! c( H" n, g& i% e
{
' k' q+ Q$ X* D" W9 _9 uchar *buf1 = "BBB", *buf2 = "bbb"; - c3 i1 u% K- X3 p) y/ w
int ptr; m/ v. ^$ f' Q
ptr = strcmpi(buf2, buf1); 
% M/ I: ]& a3 _if (ptr > 0)
# q8 {. c2 R: a. X3 bprintf("buffer 2 is greater than buffer 1\n"); 
) L' H) ]1 n+ b1 A4 U& d+ G* t& }if (ptr < 0) 7 q2 N, H$ ~3 R3 y
printf("buffer 2 is less than buffer 1\n"); 
' b5 V$ a/ ~' i- L1 I+ Fif (ptr == 0) * a9 z6 U' N8 o, @4 V% f' B& z
printf("buffer 2 equals buffer 1\n"); 2 O9 {- q# ^, a; m- S" f/ w" ]) Q
return 0;
# O* c- e2 }5 r4 A}
; X, R2 e2 @6 ?. M6 S8 K/ X- o. p6 ]6 ?7 y5 D4 Q7 J
1 R5 r. F- @- {& H3 i1 G( @) M

5 d% N. n2 v3 b函数名: strncmp + H8 I( g- j2 Z- j7 E3 j
功能: 串比较 - d; i. N! V% E$ T8 o6 {
用法: int strncmp(char *str1, char *str2, int maxlen); ! I. e. v3 ?& X) v
程序例: ' H1 @2 ~7 ^8 s4 [- J) Z& l
#include <STRING.H>3 ]' x6 P6 Q( u) e, A. X& ?, E3 g
#include <STDIO.H>
int main(void) , c! E# A+ w: Z+ _
{ 3 p+ N% N/ q0 g1 K4 h- K5 M5 I* ?- }
char *buf1 = "aaabbb", *buf2 = "bbbccc", *buf3 = "ccc"; 5 `' a; d2 C/ S7 }+ g
int ptr; 
, s+ H0 R8 f0 J! Nptr = strncmp(buf2,buf1,3);
. ]( O$ s6 t( sif (ptr > 0)
- W1 X( \9 a* T( C$ t8 ^! qprintf("buffer 2 is greater than buffer 1\n");
5 }% G% x# L/ B2 x8 celse
! V9 `$ c4 y4 w2 X6 t* R, {9 M, lprintf("buffer 2 is less than buffer 1\n"); 
/ T0 S/ @; a6 x" f& {0 n7 Vptr = strncmp(buf2,buf3,3);
( G$ v }2 o5 M" c2 b( kif (ptr > 0) # X/ U' Q( v; ^* I- `
printf("buffer 2 is greater than buffer 3\n");
1 Y, H( W9 g# @5 C$ L8 ~9 p% lelse 2 E' v! m( C+ Q( g) ~% u }
printf("buffer 2 is less than buffer 3\n"); ! U! [: r$ K7 d( W' g; w
return(0);
4 L% x' ^6 S7 U! P7 A8 J7 M8 M7 V}
' u9 Y! E: o- R( w; m, c
) `7 M! q5 S% |4 ~) ?7 Y& _8 o0 ^8 L2 E
8 Z9 g4 d& P* j9 R& R& M% ]$ P函数名: strncmpi 1 d7 z( O: U9 y- j' S8 k/ }
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 + r. e+ U& ?% F4 h. s a+ f5 X
用法: int strncmpi(char *str1, char *str2); * `2 T5 C( ^/ i, c7 C; S. k( N
程序例: 
( ^0 p! d' {3 B* k- H#include <STRING.H>
' y3 \* }- w- C( M+ J#include <STDIO.H>6 J7 v/ C/ [+ {, @" K# B
int main(void)
: f% R2 |9 s4 ]0 q3 {/ \{ ' }* f. n1 Z* z5 n4 r: n
char *buf1 = "BBBccc", *buf2 = "bbbccc";
$ ~2 E$ m$ C7 P5 N+ c) {int ptr; 
/ V& q/ L8 y+ d, u, Kptr = strncmpi(buf2,buf1,3); % r# O% U% {6 Q3 T# N" v
if (ptr > 0)
: O; M' i$ |* S3 hprintf("buffer 2 is greater than buffer 1\n"); 
$ L4 t" |/ g' o8 Wif (ptr < 0)
3 p0 K+ a$ {% U3 ]& _( y8 [4 b- pprintf("buffer 2 is less than buffer 1\n"); ; h$ O) K6 C% Y. ]
if (ptr == 0) 9 `6 ^+ ~4 b5 B+ M0 O
printf("buffer 2 equals buffer 1\n"); 
& ^8 P. d2 g% x# h% ?return 0; 6 B1 ~. E$ {* V6 U# d2 a
} 1 \/ v; V j' r+ H% B( S
6 ~1 {7 E- T: h0 _: J; W

# A# r$ f" x) G7 f: l) R& @函数名: strncpy 
- m6 e0 v0 @4 A8 O功能: 串拷贝 , w# b6 W% F8 l0 h8 f) u$ z/ S
用法: char *strncpy(char *destin, char *source, int maxlen);
5 g j- N" c' X4 k8 k* o程序例: " _2 B+ O6 k: [$ Z+ i1 m8 [6 F
#include <STDIO.H>
! r5 E! [& c! ] D7 m/ c/ e4 g#include <STRING.H>) ]) W/ y4 w8 i; K. r9 Z/ ?6 B- D" N
int main(void) + O, y' N- `9 o) M4 {' [
{ , |5 v+ B" j7 T# S- X, u# r
char string[10]; 2 W4 z; i* A! v3 P4 D. v ~6 {
char *str1 = "abcdefghi"; 
- A4 E: B* P0 J2 }strncpy(string, str1, 3); ( |3 Y4 [0 U5 D X3 i
string[3] = '\0';
# c! P. Y1 h( C8 C) u9 Uprintf("%s\n", string);
" ^; x) d. i, r% p3 R/ g U' Treturn 0; * v) Y! K3 b$ _
} , j# c- d0 Y5 e$ _. q

" Q- s3 L+ N. D% U2 B4 r) S- o
0 b8 |3 \, R/ q1 v# P函数名: strnicmp 
1 O8 j0 o& o- W; c/ c# S; f: d功能: 不注重大小写地比较两个串 # W! M: T4 |/ O. e" s5 T
用法: int strnicmp(char *str1, char *str2, unsigned maxlen); ) G* ?" R, C& c2 p
程序例: 
7 b, \- g+ v8 |0 N. _$ t#include <STRING.H>7 q- T0 y. y8 _
#include <STDIO.H>8 J) R9 g) c4 Z# m( V: U/ _
int main(void)
! f" h" t. H1 q6 Z: i{ 4 u& E/ e0 r+ [$ N8 P. Z
char *buf1 = "BBBccc", *buf2 = "bbbccc";
& }1 O. P6 n; S$ v$ I' {8 ?% ]int ptr; 
4 M& i. K7 h0 b+ |8 y5 ?ptr = strnicmp(buf2, buf1, 3); 
4 `/ Y7 S8 e6 E' [$ @if (ptr > 0)
4 e8 X/ c0 ~: e% r* kprintf("buffer 2 is greater than buffer 1\n"); : f- O( B V9 G8 E }( X2 B' K
if (ptr < 0)
% ]: W" g5 k8 c+ kprintf("buffer 2 is less than buffer 1\n"); ! B9 c1 m, G! O% _9 g
if (ptr == 0) 8 r% e. }8 [ R) T* Y9 m, ?, G
printf("buffer 2 equals buffer 1\n"); 
. w, ^2 {; v* b$ E, Freturn 0;
0 E Y) I5 @9 \1 ~}
% {0 I/ F3 v; `/ U u! m
1 t( N7 c3 u- b+ Q5 O& P
; J" B1 |$ i8 X8 }
 K1 A, o: s7 P' ?# ]" I函数名: strnset ; |3 I" w. X9 q0 q
功能: 将一个串中的所有字符都设为指定字符
9 y$ Z! j' h6 k/ n用法: char *strnset(char *str, char ch, unsigned n); % Q, U- a1 t* T1 j2 ]: K
程序例: 
* z7 f" }# x; Z#include <STDIO.H>% S1 u2 U" j8 R$ r" F6 D
#include <STRING.H>
" [) U+ @; S! ~2 ~" V+ K3 J4 F0 Tint main(void) " V* V. Y# S2 K7 u- P: a/ h% q
{
4 c7 w9 P: h6 Gchar *string = "abcdefghijklmnopqrstuvwxyz"; 0 P# y% d* q! M6 Q
char letter = 'x'; . W+ |* ~6 J3 |
printf("string before strnset: %s\n", string); 3 [4 q# E6 F9 p1 r
strnset(string, letter, 13); ( B% m& X( S: R
printf("string after strnset: %s\n", string); 5 V4 P8 P: V, T5 a0 L* x( f
return 0; , ~7 ?1 T# ~( O7 p- ~
}
' z/ {! o/ z% m) H0 N) R' @9 Q" {' @+ n; z% ~
1 C# E7 F+ I, Q M
函数名: strpbrk , Y% K: F) T7 b5 z4 G
功能: 在串中查找给定字符集中的字符
7 I% X; P* Q( m# N3 J |用法: char *strpbrk(char *str1, char *str2); * |3 {. \* G( s1 n: T
程序例: 
' f3 l P2 s, Q/ V#include <STDIO.H>1 `9 Q9 R& C9 A1 n) {6 Y2 l
#include <STRING.H>" z- h8 t7 X( r7 {. `' R% `
int main(void) , m, b. O4 J- n+ f5 g
{ 6 F6 c9 Q, C, m- V8 Z
char *string1 = "abcdefghijklmnopqrstuvwxyz"; # M, L5 Q: {5 q4 C4 X/ w! r
char *string2 = "onm"; & @4 c9 {( f6 ~
char *ptr; 2 c1 `6 z0 h9 K& V9 o+ S
ptr = strpbrk(string1, string2); 
* H# M% [: l1 ]& bif (ptr) 0 Q% I: B: f5 B4 ~7 C+ j4 b
printf("strpbrk found first character: %c\n", *ptr);
& x* q- r& P0 e4 d& l" velse
6 m4 @, v8 u7 b5 \printf("strpbrk didn't find character in set\n"); 3 I" ~7 I; ]" Q" n0 w
return 0;
( ~* D1 n; ` l7 y! {+ F# z6 y}
4 h0 S5 k0 _6 u3 B0 E- t- z' w5 N. s8 r7 Q2 v& U1 j! ^

2 y# J8 P) ^# z; t1 G; c$ K1 Q( u1 @3 |. {5 A& ]
函数名: strrchr 
( D S% ^# s' ^5 f/ J! j* Q6 K功能: 在串中查找指定字符的最后一个出现 & j$ ^# v( b4 a
用法: char *strrchr(char *str, char c); 2 v7 I! a8 S, c3 w' o
程序例: 
* F# I& I* a3 v. ~6 O7 I#include <STRING.H>3 }! {5 [' U! J6 J
#include <STDIO.H>
% n# c! W, G) g, ?. o7 T8 cint main(void) & }( m- b) h! T: Y2 ]! ^ g& F
{
0 d% I7 U+ T) v) R5 t7 J" M* zchar string[15];
% S, o% `' R8 achar *ptr, c = 'r'; 
 S& s# e3 X, `) Z3 @- V0 K0 ^strcpy(string, "This is a string"); ( g& y6 r7 y* U6 o3 n
ptr = strrchr(string, c);
9 N9 o$ L W9 h+ a" Kif (ptr) . q* `1 s {1 I' W
printf("The character %c is at position: %d\n", c, ptr-string); . T. g, w7 x, B
else
* S3 ~. Q0 E2 t6 d6 H& A* \printf("The character was not found\n");
- S& h* a9 X- q: A( t1 Ureturn 0; + D8 M( {2 }3 b6 v. Y/ [& a
} + A3 b* B( J4 g! `4 s& i

! b; W1 e9 M2 D1 ~9 i
. U2 b, [( j. M+ Y
# u( O+ U% V" z, O) v函数名: strrev 
. H; W `* j( n: F0 n功能: 串倒转 ! G" s: Q F2 a6 E. Z9 S3 G
用法: char *strrev(char *str); u% X" e4 m" k3 X+ X
程序例: ' w! K; |! b& G0 ^! |2 o5 N" v/ y
#include <STRING.H>' k, s g) J* X7 \* }2 V& E7 R1 r
#include <STDIO.H>% J& F; ^' {& ~$ d( U+ z5 C
int main(void) $ A, d3 n" }" E
{ 8 w( x/ ]( p4 R
char *forward = "string"; 
; D# N3 O/ Z" x. `% ^# Tprintf("Before strrev(): %s\n", forward); ) M" L7 Z6 Q3 Y# C: N
strrev(forward); u5 y1 C1 p. R4 j' V& ~
printf("After strrev(): %s\n", forward); - U- m# f2 ]1 V, H! {$ C$ L
return 0; % o5 {6 v; ?6 I- n" b7 T$ d& {' R
} & ~. U" {9 n% A1 H9 z4 r8 B
9 a% e9 g% D+ U6 u# W& D8 H
函数名: strset 
/ O% z6 L4 N5 N/ e6 ] P功能: 将一个串中的所有字符都设为指定字符
, G- N2 `3 q1 b用法: char *strset(char *str, char c); ( g* T6 X# W# }/ W) S
程序例: 4 ^/ j6 P- l6 R
#include <STDIO.H>/ X3 j% c; d% M4 [/ T0 L/ h
#include <STRING.H>
7 v- c0 |9 Q* c4 f5 ]0 [+ ]int main(void) 0 w* I+ Y& {) n/ x& A' j9 i) s+ V
{ ; d4 a3 ]' V5 f2 h$ b) k
char string[10] = "123456789";
9 { U/ k. W; a8 ^char symbol = 'c'; 
printf("Before strset(): %s\n", string);
8 J3 Y4 |+ u0 {6 H+ Jstrset(string, symbol); 6 E! q+ J+ I- l" a8 e9 x8 K- B' k
printf("After strset(): %s\n", string);
7 [0 K% F3 V& q% creturn 0; 9 C; @( R; Y" t5 j. s( d
}
. @1 R' k k% V0 Y$ a! S3 j* d( P4 K: J1 _0 ?8 R
% I% y/ U5 W0 x. F- k2 D

$ Z7 C8 H# z h$ D7 r+ h& Z函数名: strspn 
& W( g3 j7 m" i' g) K0 i' c, z u: o功能: 在串中查找指定字符集的子集的第一次出现
- `1 n6 h+ }$ E1 j H; T用法: int strspn(char *str1, char *str2);
" }1 \6 d+ C$ G U6 w5 b程序例: 
) `* y- Z7 P$ h' j8 T# Q#include <STDIO.H>( y" I5 j5 W+ O
#include <STRING.H>
5 ^; H& ~/ ?/ K6 X7 Z* n n$ d#include <ALLOC.H>
4 W; F$ ?$ ~2 Y2 l+ Fint main(void)
7 [# H9 X' F- W: T, Q, s{
5 Z* G% J& J6 t O( Vchar *string1 = "1234567890"; ^+ N3 w/ g; D7 ?6 ^1 |8 U
char *string2 = "123DC8"; , v* @6 _# K( {7 I& I" E
int length; $ l8 \" P( [' q+ T( k& N+ n& _' g: g
length = strspn(string1, string2); 2 a5 }0 N4 U" M
printf("Character where strings differ is at position %d\n", length); 7 @: t' i( D7 b5 {8 J5 R1 j8 c
return 0;
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7 y5 ]( O" T0 I. J
函数名: strstr 
 ?! d3 z0 G7 H功能: 在串中查找指定字符串的第一次出现 2 |6 e8 |1 Z3 O D+ L
用法: char *strstr(char *str1, char *str2);
0 d8 D) M! @0 I* O: c; Q程序例: : n$ m& h# `8 Z8 i$ H
#include <STDIO.H>6 d! W+ [9 F1 d- d t: G7 N9 [: d+ _& q( j
#include <STRING.H>: ?0 w8 R' S+ m7 s. I) T
int main(void) + Y0 ?2 r% u; c3 O6 \+ D9 c9 }, O
{
% v4 w) P9 m; Lchar *str1 = "Borland International", *str2 = "nation", *ptr; ( v2 u! ~- a' S5 f( v: x
ptr = strstr(str1, str2);
4 r4 m5 V% N' G7 D+ Y, K mprintf("The substring is: %s\n", ptr); - w; m- n! M3 a$ V, F+ v: x1 d* B
return 0;
/ f1 n4 m7 A: S$ X* K. x} 
! ^, ~. u+ ~! g( O9 H4 {# M. X c# F- m' I" O

8 c a% U# R" B6 A1 a/ B6 G函数名: strtod " ~( v( U* n% t% v
功能: 将字符串转换为double型值
0 T1 N7 g! s' x% v& L用法: double strtod(char *str, char **endptr); # B3 j X/ p/ h$ G& I/ ~
程序例: 
' E, ~* q" E6 J1 `#include <STDIO.H>
" z% |2 a( {' N+ Z. z2 {, ]#include <STDLIB.H>4 i! w2 e5 W! w
int main(void) : g& N4 j/ \, Z9 a& n2 E& \' K
{ & k4 ]3 g: O$ i9 C8 Q
char input[80], *endptr;
( ^% r% Q& q# o; m# z. J% l f, Tdouble value; 
" @2 Q* A& \% C* u4 Cprintf("Enter a floating point number:");
 a" L5 ^: g2 tgets(input); 9 G! g ~# \9 ]4 M$ @
value = strtod(input, &endptr); * C# \9 V% K Q9 g; k \ v
printf("The string is %s the number is %lf\n", input, value); / e2 O) W6 c- A( t7 L S/ S: U" T7 }4 @
return 0;
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5 f. g. }5 R8 ]. l+ h5 \ [/ u* G- Z/ P

: V/ w! v: u! L. i$ h4 b Z( _# {( ?- e! n3 ]
函数名: strtok ) \. o* Y; j* X, P) |8 Y
功能: 查找由在第二个串中指定的分界符分隔开的单词
- v1 A) Y; v3 Z+ _' z: O' ]" j: A用法: char *strtok(char *str1, char *str2);
8 ?& h2 _# G+ t) s1 `3 t程序例: 
4 u1 c* T# T! \/ \/ S2 Y#include <STRING.H>
9 U* E1 H* H- R9 C9 s#include <STDIO.H>7 g. `3 Q" h1 F# a5 q6 l2 C& s
int main(void)
3 S( P9 ~+ a' t, E% q{ & ^9 y! R& r% @: ~3 U4 F
char input[16] = "abc,d"; , R, H+ S+ L9 P; ^; M/ f$ `# L8 i
char *p; $ z8 z9 D& Y) C! u* O5 y m i5 u, z
/* strtok places a NULL terminator
% v% T# ]* z" ]) hin front of the token, if found */
' b2 ~) F( D- Z: Wp = strtok(input, ",");
( g% A* w$ V; O1 oif (p) printf("%s\n", p); + Q% v- }) B/ b) J( b+ {
/* A second call to strtok using a NULL / ~5 q* u7 S( }9 D: `* R
as the first parameter returns a pointer $ @$ S) h# M X& K4 C7 c+ J# b
to the character following the token */ ) _* T7 Q/ E1 y; g. ~3 T5 o( ]$ A1 _
p = strtok(NULL, ",");
( Q; q( i, {+ D9 Tif (p) printf("%s\n", p); ( Y5 ~' ?1 s" w1 B
return 0; $ { a R; T8 K2 o
}
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$ p6 m4 }8 L i e) p( x4 W$ ^

" Y* M+ T3 [+ c0 T- H) F8 w5 M" m6 }函数名: strtol 
! w l* |3 l# |0 D$ x* h% N3 H% U功能: 将串转换为长整数 1 f0 s. Q/ A4 m
用法: long strtol(char *str, char **endptr, int base); 6 U Q% V6 K; q) F2 z5 {0 U7 M
程序例: # @( i9 @/ D# r( H! a( H
#include <STDLIB.H>8 I: w, J% V* h- {9 q y9 L
#include <STDIO.H>
& r% T" P! C7 r; o, ]3 q6 Mint main(void) 2 k9 s2 j3 p |
{
" w; V( b: d1 A1 s! I6 I8 Qchar *string = "87654321", *endptr; . N$ Z6 ]- c* U% s) t$ y( I t
long lnumber; 
% z0 E: H( j& C7 b8 W/* strtol converts string to long integer */
5 S% Z9 R. @8 {" g) flnumber = strtol(string, &endptr, 10);
+ J: h* k. N5 r# ^5 ^6 ^printf("string = %s long = %ld\n", string, lnumber); ) n6 Z# t$ n& m- ^2 ]4 z- ~
return 0;
4 {: u, _" |. i) B- J. [" M} ! k' R6 C+ |, j$ R6 Z- S
% p4 {& \* U" P; \5 K
函数名: strupr 
9 S2 U; v/ i' G5 p功能: 将串中的小写字母转换为大写字母 7 @& z1 `0 \: T: Y6 r0 a- S: ~
用法: char *strupr(char *str);
+ p/ J h$ d' X# e- R' k0 H4 Y* m; \程序例: 
* q7 |$ r# N3 O' `- _) V#include <STDIO.H>, B$ n7 {. |2 B) a* c O. Y8 `! L
#include <STRING.H>0 m2 c- A9 N6 e" n
int main(void)
6 o% i- I q! q- S: V( M{
/ n0 Q; {( `3 q3 s7 ~- y7 qchar *string = "abcdefghijklmnopqrstuvwxyz", *ptr; 
 A/ P4 o9 O3 v# c5 n/* converts string to upper case characters */
) A$ [; `+ B, h5 x2 i; y- D) S$ jptr = strupr(string); 6 @$ P9 C3 n `5 m! z6 }% ]. F4 M4 [
printf("%s\n", ptr); $ V. H/ P2 A% E; ?9 U: ]
return 0; ( }9 P% D7 O& S: C8 u( h; c# w
} 5 \9 ?; o; v5 O

' B, H% K. r" a8 k H. O2 F
4 I, w7 s/ x* ~$ f8 \0 X- d5 ^* Q
* e) n9 l, l- Q$ p函数名: swab - a/ y: G( q+ d! d8 r: }
功能: 交换字节
8 T* D# L1 ?+ L4 F. B用法: void swab (char *from, char *to, int nbytes); & e" |' r$ V; w9 p& B
程序例: # }+ F7 g D! g+ I
#include <STDLIB.H>/ y2 q2 J% i8 d3 j/ B0 B, |
#include <STDIO.H>
) K @; p% b2 I* X6 R2 ]#include <STRING.H>' D/ j( I. n: U5 s+ E& i; ~
char source[15] = "rFna koBlrna d";
- h: \6 J0 s0 F v j+ Nchar target[15]; & C/ ]0 p/ x1 ~7 R' W
int main(void)
% k" F: r9 v {( m" ^& O# a{
# q9 Q5 [( j# J" J- sswab(source, target, strlen(source));
9 q! e# x- g2 v; sprintf("This is target: %s\n", target); 9 P/ { T3 R$ e I, W
return 0; 0 `# h% q" s$ \1 s. C) v V- u
}
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; G9 p1 b- D/ I7 t2 o4 ?" E) }
4 v1 D) X9 e0 i, n- B) w' A
函数名: system 
; Z$ f* a) W+ m功能: 发出一个DOS命令
! ]# m v: o" \/ L1 y/ P. ^- s3 Y! B用法: int system(char *command); : H$ T* b5 M& G. H: s8 l( v
程序例: 
# y" O2 [5 U( @3 _4 \#include <STDLIB.H>% c4 b4 n w6 w G& p
#include <STDIO.H>! d$ {$ ~+ Y$ I2 r' J* F
int main(void)
* N v. D7 ?5 Q5 ]1 V( Z" J, j{ 3 q8 q7 ^4 w7 N
printf("About to spawn command.com and run a DOS command\n");
% \" \# B6 J! j& B, Msystem("dir"); # Q1 K7 H, T( X' a
return 0;
. m" ?* a4 h& O; T* ?} 

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