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); 
% e! r" ]! O& ~- S$ }; V/* display the gray scale */
5 N) b, k* b, c# v& j; Ght = getmaxy() / 16; " R2 E; v$ v( t% F. S( U
xmax = getmaxx();
' A2 j6 I5 \) W3 t$ `, Ay = 0; ; ]% D- p% S* n& ?% i7 Q- z U6 Q' m
for (i=0; i<PAL.SIZE; {
! w% s5 ~& X% H( }% fsetfillstyle(SOLID_FILL, i); : |- s" c/ @% D. t0 r3 O6 d
bar(0, y, xmax, y+ht); ) M! }2 |; u- J. Q* E( l
y += ht;
( n" ]* U5 m8 e0 N} 
) z7 E" z8 M$ ~/* clean up */ ( @, M3 Z9 Z* V: N( n
getch();
* t! D; R8 K6 M3 m" [ I. D- m9 cclosegraph();
% I; b F J% r, c1 \/ u! I$ Ereturn 0; : g, g3 D; V6 `) ~% i( A- p
}
) C3 G" K7 O n5 ~- X6 G$ }" {/ @& i) {% h

4 L1 K; I! v. v7 Z5 b5 p% ^) f$ b4 H/ j2 ]1 h* z
函数名: settextjustify }* `) F" f" o4 h
功能: 为图形函数设置文本的对齐方式 * e1 Z( }& y& v: w8 z+ e# T
用法: void far settextjustify(int horiz, int vert); 0 y2 W. T- h9 J4 p* r2 M
程序例: 
& D8 X( Z/ g2 [, q! r# ^#include <GRAPHICS.H>
, Q( L5 W4 i. U3 `, e! U#include <STDLIB.H>% t5 H$ P Y& I4 C p. ~& p) R4 M
#include <STDIO.H>' X6 l, o0 {" O
#include <CONIO.H>
. u+ _# N4 z3 M) M8 C' i" K/* function prototype */ $ Q" ~$ x+ x) i) S
void xat(int x, int y); 
4 D Q. m/ [2 q) I% O X/* horizontal text justification settings */ : s: b" c4 Z& P/ S* d& L6 J5 Q: Y
char *hjust[] = { "LEFT_TEXT",
/ B! M& t6 }, `1 a' J, _"CENTER_TEXT",
; X) w' i% D, X8 v"RIGHT_TEXT"
: Z; K2 j1 F) y+ Q* j m, T}; + j4 s) b: P7 S, e5 v2 l
/* vertical text justification settings */ 4 c0 c W- u O, o$ C; L) k- `
char *vjust[] = { "LEFT_TEXT", n7 {) V* V: Y# e2 w
"CENTER_TEXT", 6 B/ i6 ]* M$ d6 M+ r6 ^7 \
"RIGHT_TEXT" 6 @3 ^: o" I- ]5 a" M0 I+ `" \
}; - b$ C4 j9 p8 |' n$ j$ |
int main(void) ) a" H8 l) f: N6 L' M
{ . ~; q1 q2 L( R
/* request auto detection */
0 a7 q+ p$ q" q$ D' d; O1 W" Xint gdriver = DETECT, gmode, errorcode; * }/ R& [( f/ ]4 e
int midx, midy, hj, vj;
0 A9 n( ^5 O: k b* zchar msg[80]; & z8 s1 C. Y$ u7 w& j
/* initialize graphics and local variables */ 0 z$ l) t& B. f3 G
initgraph(&gdriver, &gmode, ""); 
8 ~5 S2 k6 y* ?' f; ~% G( h/* read result of initialization */
' f8 O/ F- r8 ]3 o- Berrorcode = graphresult();
: J* i2 S4 J+ G; ~! n) F% A9 \0 Oif (errorcode != grOk) /* an error occurred */
0 b8 u: p2 q+ P{ * k6 V- {5 X1 t! d4 x5 Q9 V1 t
printf("Graphics error: %s\n", grapherrormsg(errorcode));
& h0 r% i8 W5 j3 o6 I9 n: Gprintf("Press any key to halt:");
. e) r5 b: u* h; z _* g2 s4 c4 Lgetch(); . u0 K* r7 }- z; K
exit(1); /* terminate with an error code */
4 U4 M6 D+ {' j# {} x j9 T# N0 t1 v" j
midx = getmaxx() / 2;
2 z9 B# F: S* Smidy = getmaxy() / 2; ( B% J" ~8 U5 y% A$ Z: l
/* loop through text justifications */ " l3 `% ^+ G# J( ~% k4 w5 ^* _
for (hj=LEFT_TEXT; hj<=RIGHT_TEXT; hj++) / Q! V5 m& P ^/ j) _$ E
for (vj=LEFT_TEXT; vj<=RIGHT_TEXT; vj++)
/ Z5 o: a% [2 }, [0 J{
, s) v% z5 Q( T) lcleardevice();
! i X9 {& ]% k, P/* set the text justification */
- F2 y3 Y6 n4 g& rsettextjustify(hj, vj); 
' |1 Q" A" m" l/* create a message string */
; ]( ^ \0 a: {$ \7 k4 Bsprintf(msg, "%s %s", hjust[hj], vjust[vj]); 
0 H) n/ x) q Y4 ^/* create cross hairs on the screen */ 3 h" S; M t+ E( _9 B
xat(midx, midy); 
7 Q$ K0 r# |, m9 s/ C \/* output the message */
. X* k" [1 B4 \! vouttextxy(midx, midy, msg);
8 E. r% K% r0 S% T6 [2 j" E& j' X( bgetch();
& [7 j2 {% p" Z" [# Y5 W9 Y: L5 s} 
; v% @7 I; f- w' h: S6 I0 r/* clean up */
; G, J# D% ~" p: |' C/ Rclosegraph(); 9 X2 z x- p$ c5 ]6 U
return 0;
, [- X" R, k3 Z} 
4 d3 x3 D: r# p5 T3 z- n/* draw an "x" at (x, y) */
# r; W% m! w5 z2 Cvoid xat(int x, int y)
. E7 E1 x6 A! H) f% x{
1 B4 q7 S, D7 S! ?line(x-4, y, x+4, y);
8 _% Q0 t4 [7 M2 Cline(x, y-4, x, y+4);
' O- z2 X) b0 I) ]% [0 T V} * [3 Q+ v7 [5 q6 |+ ?

+ D* o9 g5 H) I9 i
5 _" X! ?3 A! c! R# M! V" Y+ _* }函数名: settextstyle ' e4 y6 Z# i& ]+ E! ?0 {; i4 X2 n
功能: 为图形输出设置当前的文本属性 - d: t. w4 P/ P) a* J4 Q
用法: void far settextstyle (int font, int direction, char size); ' w: H% x& t8 t- C6 X! E P& t# o
程序例: 
, c. D5 d) m: O) _ O#include <GRAPHICS.H>
1 b$ E# ]# Z% G! n" A! i! O! F#include <STDLIB.H>. l1 V: H3 z: j, T4 A. `. o$ p
#include <STDIO.H>! L$ g7 N* A8 u1 \4 u/ ^
#include <CONIO.H>
3 t/ z+ ^% I$ l" N) A, O C$ @2 x$ x/* the names of the text styles supported */
' y9 l7 T5 a( ~' y2 ^5 @char *fname[] = { "DEFAULT font", " G9 w' m) R' Z2 M( c& J
"TRIPLEX font", 5 I8 N- L c! Y- _; Q, }
"SMALL font",
7 T ~- y5 y6 O$ c2 z" ^9 Y"SANS SERIF font",
* [- i* a; C& J3 l( v8 t# [/ ?"GOTHIC font" 2 @ W D. \/ z# `' @
}; 
$ X- A: R# o: @' e; B0 qint main(void)
! u3 G) u& L! y* p( n8 C2 \2 q/ _{
3 q& U4 o( _/ K* X" n- m/* request auto detection */ ' q( i& H' g* w" [& ]. P' U. s
int gdriver = DETECT, gmode, errorcode;
/ z5 D0 {& Q0 b Dint style, midx, midy; $ H$ T% @+ c* @
int size = 1; # ^2 m6 O3 V3 L7 r. w
/* initialize graphics and local variables */
4 e7 f- Z8 G3 U) Iinitgraph(&gdriver, &gmode, ""); 8 z( h% R, `& j& a
/* read result of initialization */
8 B( D5 Y4 M, T2 m, uerrorcode = graphresult(); . U2 h+ p8 v5 n+ x3 ]% W% l
if (errorcode != grOk) /* an error occurred */
# b3 u5 I: u5 g p# w: L{ X. |5 y& s1 E2 W3 E' M
printf("Graphics error: %s\n", grapherrormsg(errorcode)); ( o8 I$ N$ {! l
printf("Press any key to halt:"); 9 U7 V, R2 Z- G; L! ]8 j$ J& c% p
getch();
3 M3 J I1 ^" lexit(1); /* terminate with an error code */ 6 }/ G% e+ {# q2 C) G/ V
} 
: M6 t" a& {1 R8 d) R% [1 umidx = getmaxx() / 2; : D9 n' Z2 T- I" \3 [5 k
midy = getmaxy() / 2; 
6 {) ~) V( T* y8 {) S- Ssettextjustify(CENTER_TEXT, CENTER_TEXT); 
! g" H( N% p/ [/* loop through the available text styles */
) p# B l* T+ |9 S5 Q/ ofor (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) - \# {8 X8 Z6 g4 g
{
, @ t! E, M( s$ r+ xcleardevice(); , x" Y% v4 W6 e
if (style == TRIPLEX_FONT)
( [/ L- c+ v# g! Osize = 4; - U5 v! ^1 `; W5 ?* M, t' H
/* select the text style */ % ]" Q5 L8 r( Y( v4 k6 c$ R0 J8 K# I
settextstyle(style, HORIZ_DIR, size); 
3 b! X7 ~+ }& c Q4 i0 h* V/* output a message */
" o6 M+ `! R1 Bouttextxy(midx, midy, fname[style]);
1 t6 q. a7 [. v6 q7 D$ [3 Hgetch();
2 f7 j) Z; \$ D5 c+ j} # U( A2 j4 \9 ^
/* clean up */ ; V, g6 S& S3 w3 l& Q% J; ~
closegraph(); " m# C6 S3 n* q7 a$ z1 O
return 0;
0 z" R1 J7 {1 w+ }1 H}
! |; Q2 t( Y' {; Y: Q5 e3 q1 B, V O
2 X9 h% C! q5 ^* I9 |
函数名: settextstyle 
7 s% ]9 @/ n/ x8 h+ |& h功能: 为图形输出设置当前的文本属性 # b R; R/ |5 K7 v2 H. n8 U
用法: void far settextstyle (int font, int direction, char size);
* ]5 U+ T3 T" f7 s* f1 J程序例: - u$ k2 u( P( [. P
#include <GRAPHICS.H>$ e \6 b- ~5 I9 _& a
#include <STDLIB.H>
: t, d5 z3 ^# l% b1 Z u3 M. v#include <STDIO.H>
# j& i7 i+ A. r- H) Y4 Z#include <CONIO.H>' j6 @, j j5 G# F, T) L* x
/* the names of the text styles supported */
* \6 W) D! R8 S, m2 Y5 E* {char *fname[] = { "DEFAULT font", ' l3 X* f& C! y% a3 ]: G
"TRIPLEX font", 3 b5 d5 m$ b3 V; K, R
"SMALL font",
: B" M6 m& M( ]& n g+ X"SANS SERIF font", & H' c6 ]* w0 u5 P8 U& t2 r
"GOTHIC font" 3 s5 S( p$ z2 Q. K% q+ O
}; 
4 _ c0 I* g$ ^) W. Zint main(void) 0 e- d" A: i; \9 a0 e% i9 L R, O
{ 7 m5 O) {$ X) Y9 l
/* request auto detection */ , V1 K: A7 Q. F, P
int gdriver = DETECT, gmode, errorcode; 2 I% d$ X! Q' P9 Y6 m2 I( s8 k% W
int style, midx, midy;
3 I1 x4 e. Q" P5 ]- }int size = 1; 
, P+ k, n+ x5 @3 D. ~/* initialize graphics and local variables */
/ F' S' f' e* B8 n1 l; }initgraph(&gdriver, &gmode, ""); 
; C: I4 e8 L) I/* read result of initialization */
7 |5 u0 G* z( X4 [: Perrorcode = graphresult(); ' \7 B& N0 c8 m4 _( l
if (errorcode != grOk) /* an error occurred */ 2 u4 [, ]4 n- W' n% K
{
* H# k9 e0 b- V ?6 [! F: Hprintf("Graphics error: %s\n", grapherrormsg(errorcode)); j* J3 I5 ]3 a8 L O% `* U5 C: S
printf("Press any key to halt:"); $ e/ l5 d% c* a; i6 p* V
getch(); % |% T* m* j* G9 w
exit(1); /* terminate with an error code */
. ~* \0 s! d0 q, v; n} 0 @8 l9 {2 c. J* ~2 X' R5 U, K
midx = getmaxx() / 2; 6 a0 s5 N' K# S) s2 B5 w* _9 |
midy = getmaxy() / 2; 
/ z# U) m8 |6 c7 C( wsettextjustify(CENTER_TEXT, CENTER_TEXT); 
$ y _1 k8 k" j) d, A/* loop through the available text styles */
4 F# m `! ^& yfor (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) + p- h+ O* V2 |. n; O+ A( U7 g
{ " I P0 n6 y9 I6 a0 x' D
cleardevice(); 8 B8 d- r! G. q" [+ |
if (style == TRIPLEX_FONT) 3 O2 Y; d, X' y
size = 4; 1 L! _) V& @# F2 Z1 H5 x
/* select the text style */
! ^/ j( Y9 m" P: t1 Gsettextstyle(style, HORIZ_DIR, size); 
% s+ f' D/ S/ i6 O/* output a message */
7 n1 _3 {9 l$ Uouttextxy(midx, midy, fname[style]);
/ }3 `! F! m& d; tgetch();
: s8 Z* x7 G( ]3 V- W} 4 f# B* z: Z# y, A4 _3 C: W3 b
/* clean up */
5 K$ ]' z: ?2 g/ z. Z3 Q* `6 Eclosegraph(); $ x: J! {, X7 Q1 ?4 _# S9 l
return 0;
: \4 s; S9 z+ f8 Z} * H" q6 j2 F: o" j' C' z" Q

' [5 ^' r; u% ?" h. E) Y9 U& f Z# {7 c& F+ P" ?0 }' A3 {
函数名: settime 
0 C' l' J5 h. h/ b' }7 h% Y功能: 设置系统时间
 s# g* Q' J0 Q+ O2 `5 ~, N用法: void settime(struct time *timep); : g8 r4 j# D9 h
程序例: 
- C, i( r+ ^& G+ b/ x& s. Y9 l4 q#include <STDIO.H>
4 |0 f) ^8 S( G#include <DOS.H>& a7 [1 m4 P/ J0 ?9 h, P
int main(void)
! z, i9 K) y$ K0 \) \5 w: _' f' X{ # r: M! Y* h+ i
struct time t; * L2 N! L* f! u* I- d4 v X1 I3 T1 S
gettime(&t);
8 J) I- Y0 @+ o1 E9 {( |printf("The current minute is: %d\n", t.ti_min);
1 I' G7 k; F- Y0 kprintf("The current hour is: %d\n", t.ti_hour);
3 f. |, w7 b' j+ R( g5 D2 Kprintf("The current hundredth of a second is: %d\n", t.ti_hund);
! V A m: `+ w- U& C0 ^printf("The current second is: %d\n", t.ti_sec); $ ?7 m9 x; n4 T# ]! p; l
/* Add one to the minutes struct element and then call settime */
5 L/ O0 D& b$ w, ?$ a+ s- C& Ht.ti_min++; 8 a" u5 Y6 C- y
settime(&t); 
& {5 b2 X3 c3 k4 I# z7 ureturn 0; ! o1 U, M( K! T1 E; |" Q% I# H
} 
2 u0 Z2 x0 s' h; [% z F, a+ x1 h' g) p: h1 U, \/ ]) [
3 L0 T9 _2 \5 v3 o
函数名: setusercharsize 
' d2 h; j8 p% L功能: 为矢量字体改变字符宽度和高度
9 w5 Z4 J. F; J# _/ n用法: void far setusercharsize(int multx, int dirx, int multy, int diry);
9 K( o" Y7 C' G) L( U程序例: 5 L' g5 j5 |' q* M: @" c
#include <GRAPHICS.H>0 r; `. E& i1 \# ^' W( g
#include <STDLIB.H>; [ _" N1 L! ^$ x1 j2 S
#include <STDIO.H>
 ^2 N/ U0 v$ |+ K: x' f, U6 W2 w#include <CONIO.H>
- y8 ^& A+ A( M5 Vint main(void)
2 M" G; u2 u3 Z. r2 M{
' I8 b4 |' e! n) ]; p/* request autodetection */
" A0 p& ?$ L. ]3 S4 kint gdriver = DETECT, gmode, errorcode; $ [1 p8 J2 |( H8 b) E
/* initialize graphics and local variables */
' |9 L( q( P. i; n9 A( V2 s3 iinitgraph(&gdriver, &gmode, ""); 
( N0 L5 t4 r4 ?2 n: E6 ?, @7 ^/* read result of initialization */ : T0 s) r; L9 D( d# o3 r; ^
errorcode = graphresult();
4 e9 Y2 f3 E: f, t, qif (errorcode != grOk) /* an error occurred */
& K/ {! `7 p% ~* j2 Z{
1 G0 _7 n2 z) e+ I, hprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 8 j- Q4 ^3 L6 w. w ]
printf("Press any key to halt:"); 2 N- b8 |; Z0 M- D8 b$ K
getch();
( g+ g" ^6 [* Uexit(1); /* terminate with an error code */ & M" h5 c; p5 a2 S9 e" B7 e
} 
( E6 }% k% E: I2 h2 J/* select a text style */
. d' n# R) u: ~4 G# E" Z1 o) L5 t4 \settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4); 
7 h* z( O i2 T; P9 {! l9 r; J- e9 c/* move to the text starting position */ " O! t# D" e( d) K! ~
moveto(0, getmaxy() / 2); ) [+ q6 x! U1 G" S
/* output some normal text */
8 H: p" w; v. x% [9 Fouttext("Norm "); 
0 v( f5 h& i; @: n/* make the text 1/3 the normal width */ p& C. n7 U3 E& W
setusercharsize(1, 3, 1, 1);
& \8 f( a# U0 r# y- u% Bouttext("Short "); 
6 q* E( b& t7 d7 z" l' [/* make the text 3 times normal width */
 C4 c5 q" \1 D7 e' P5 \8 Rsetusercharsize(3, 1, 1, 1);
! _ ]% O4 P- \9 z! o+ _: Jouttext("Wide"); ) x# V0 Z# H; v0 J1 `
/* clean up */ ( @# G2 Q4 Q/ C# ^. z8 m% S
getch(); ) Q. ?% a# q3 X: r" K
closegraph();
6 D8 [) D- g; Z5 l4 Y# G. e5 W; freturn 0; ) F8 z, W4 \; K) Z+ g! s8 Y% z% s
} 4 B- M1 @1 N5 l$ G+ @

/ E8 N: Z+ s0 C# T, _函数名: setvbuf 1 I8 ]1 L5 @+ u9 x( X" S
功能: 把缓冲区与流相关
# x" j6 p( e, y用法: int setvbuf(FILE *stream, char *buf, int type, unsigned size);
' q4 x& X" t& r# O$ }" H程序例: 
1 P: \! |7 {1 s" n! B) O+ S2 |#include <STDIO.H>$ X! ]- j6 J# H" ]; L0 y0 f
int main(void) ' s9 D( G7 G5 I
{ C5 L% @1 a9 p6 m2 A
FILE *input, *output; 2 {6 \3 g3 \- J9 F0 g- v
char bufr[512]; 
5 I" n( Y t3 c* W; einput = fopen("file.in", "r+b");
3 D, f: J; J. R3 T/ J# D" ^& joutput = fopen("file.out", "w"); 4 E. E! ~+ n4 K9 k! v2 U: M7 c
/* set up input stream for minimal disk access, ' m' v5 T1 E7 u% }
using our own character buffer */
% g9 T4 Z$ U% r3 C7 J& Nif (setvbuf(input, bufr, _IOFBF, 512) != 0)
( v! V* Z" ^; }2 y* bprintf("failed to set up buffer for input file\n"); $ a. a% u" {( Y4 K5 ]( ~: r: U
else
: q: |+ {; \5 ^1 y! B$ j9 eprintf("buffer set up for input file\n"); 
2 k% O; z/ \5 z/ W. y/ `/* set up output stream for line buffering using space that ' t. T: s# [% I# X1 D$ }5 w
will be obtained through an indirect call to malloc */
! _5 b, e: w5 mif (setvbuf(output, NULL, _IOLBF, 132) != 0)
" L+ B+ g- m3 ^+ Hprintf("failed to set up buffer for output file\n"); . \. m) ~ J9 Q: S
else
1 U8 D q3 M$ | `$ Bprintf("buffer set up for output file\n"); . G, R5 S) G: l8 ` e v$ F9 ]# L1 _+ J
/* perform file I/O here */ 
; @% R u! ]0 }5 h+ Q/* close files */
6 P* G0 t8 n' ?$ B3 R2 ufclose(input);
. u5 M; c) k7 Q9 O+ B |% Xfclose(output);
% [0 K7 {0 L! ^/ N* T5 |& m# L- freturn 0;
8 H9 V6 \2 z6 t9 P# a R} 8 @* [" q: P2 B/ p+ T

; Y, O& W% x/ c) V( S% r4 s* ]$ ]7 q8 G% M: n

9 Y {# w: ~7 z8 } u ^% O函数名: setvect 
, D/ W1 g p& p% F功能: 设置中断矢量入口 ) f: j, m6 C! E0 \ }
用法: void setvect(int intr_num, void interrupt(*isr)());
$ M, v4 ]+ P+ t* ?* m/ V" k: r8 x程序例: , w- y2 Q3 g" _/ Y
/***NOTE: ( q9 Y" _' A6 K& U7 P H4 K
This is an interrupt service routine. You can NOT compile this 1 c3 ~! [! V2 r
program with Test Stack Overflow turned on and get an executable
7 P# ]( x( e6 T$ I0 `0 ufile which will operate correctly. */ 
# l# f8 j" x$ G0 ]4 H& O9 `5 }$ n#include <STDIO.H>4 \' h0 S1 V6 K6 {- K! J
#include <DOS.H>0 w% A7 [* \) Y6 _! W+ M, P
#include <CONIO.H>" y7 j X$ K! s1 Y1 f6 G6 P# G
#define INTR 0X1C /* The clock tick interrupt */ * W, W' _& U9 ?' I a7 o9 N f8 y
void interrupt ( *oldhandler)(void); . }+ S" d3 h4 _0 C- P( A+ V" i
int count=0; & k" R) |$ j, v, p' X" |
void interrupt handler(void)
% D- v. m; s+ Z0 _% t7 B0 W+ Z, o' a9 l{
' Y' D1 ~: ]5 h# j0 l" S/* increase the global counter */ $ e0 M, }7 e+ y( F i: ?
count++; : }+ {5 C6 ?, A
/* call the old routine */ g; j3 H( A& a$ |
oldhandler(); # ]6 V' {7 _& B3 q$ X1 ?
} 
) C6 ^8 ~0 A* i# T9 a) s& {- V sint main(void)
" l# ~1 Q3 a- J" c$ T{ . G% V% H# O0 ]* D+ N' @
/* save the old interrupt vector */ 5 j3 T" M$ Z) z
oldhandler = getvect(INTR); 
9 Q3 O" o2 j" ?2 ~/* install the new interrupt handler */
" W7 ?% r4 l- ^: W8 Vsetvect(INTR, handler); 
/ G* f8 s* D A6 i' d: c/* loop until the counter exceeds 20 */
5 U+ T1 [. |6 x- ] p3 K- fwhile (count < 20) Z! p4 o# I/ H4 }0 k7 a" m6 f& s
printf("count is %d\n",count); 
" }3 v) b- B, E/ Q( L, M/* reset the old interrupt handler */
0 Q9 k: Q& D g! o7 G' I; {2 Ysetvect(INTR, oldhandler); 
* {, Y( ]* y, v# Sreturn 0;
) C$ ^* l% k8 ?' z}
. o1 Q" O }1 t* {1 T2 u( d4 N, b% I$ a1 A

 v+ d; D: W4 U" E. d函数名: setverify 
+ O1 Q. [) ]; p. y9 d+ u. S功能: 设置验证状态
" ~ `) B- O! @; ]% q; L% f! N用法: void setverify(int value); ' U& z9 W3 k2 B0 \- L/ t* K: p, N
程序例: l `! ]. B2 {
#include <STDIO.H>
! m2 `6 Y- K* Y- P0 d3 y7 R#include <CONIO.H>
5 i1 C T! V. e#include <DOS.H>
. f& E8 H* y B( U1 Jint main(void) ) w# I. V" d7 ^. \
{ 9 ?$ l' Z: c; B+ {: r, o6 O: f
int verify_flag; 
8 x. b, x" p% |4 b5 @' m! Dprintf("Enter 0 to set verify flag off\n"); " @2 ]7 ~" u" x- w* B v; ~
printf("Enter 1 to set verify flag on\n"); 
4 T; J( P& a* [$ `$ n, W! A- Averify_flag = getch() - 0; ) ?- D5 S$ D% ?9 K# F _% |9 u& o
setverify(verify_flag); / Y+ I1 V$ J; ?; }9 h4 R% f! a& F
if (getverify()) + n, Y$ r, u( v0 \
printf("DOS verify flag is on\n"); ( q2 C6 j k0 K. L% z K
else 1 F$ K U% N2 d
printf("DOS verify flag is off\n"); ! ~6 U/ z5 F/ D$ k. _
return 0;
5 F7 m9 k1 ]9 P5 L5 J3 v: M}
* p- Z2 |/ d1 a5 [" |
' J- J$ ]5 [. m+ b* a5 m
4 L9 t% D3 t. z( T1 {函数名: setviewport # e( i ?0 u4 H. ?1 M
功能: 为图形输出设置当前视口 : [$ \4 O3 W2 C. X# `$ s& j
用法: void far setviewport(int left, int top, int right,
3 V; u2 s# P6 F! U `int bottom, int clipflag);
2 p# r. Z' X" K' I% u程序例: 
3 x j! i# i& ]3 S. N+ z9 d4 _, u#include <GRAPHICS.H>
8 z, x6 {* H t7 i" ~$ n#include <STDLIB.H>
$ J) H% W$ q9 I- h#include <STDIO.H>
, b# T2 j j6 e' c2 Q- D" P4 Y& b#include <CONIO.H>
8 H! Q* T3 y3 t6 _/ x$ Q4 U- Q#define CLIP_ON 1 /* activates clipping in viewport */ 
 e- R1 L: C# a2 b: X$ F5 Lint main(void)
8 \: V6 i) R5 d4 V{
3 W* u9 t8 P" k5 ~* |/* request auto detection */
4 p: s5 n. f: b/ yint gdriver = DETECT, gmode, errorcode; * t; z8 d/ D3 _& z0 p9 F' O c
/* initialize graphics and local variables */ / @( i/ [) O I* d2 @
initgraph(&gdriver, &gmode, ""); 
/ o( Y: E- |9 n0 `/* read result of initialization */ # a+ b% w2 g+ o" W8 y1 G
errorcode = graphresult();
# c9 B3 w% B/ O( x; e( y, xif (errorcode != grOk) /* an error occurred */ 7 K+ a2 b" s" x: L8 \$ v8 L1 v
{
& y: Q; k/ H% m" n" z2 [8 nprintf("Graphics error: %s\n", grapherrormsg(errorcode)); % G% M" n" o( ~ F
printf("Press any key to halt:"); # K4 R% t# M4 v& L% i! K7 a
getch(); 4 R% h. L5 l4 F7 o* }+ L, R9 ^ Z2 x( Z
exit(1); /* terminate with an error code */ $ n% u: E" N- W; a, r4 e
} + s: O }0 o/ t8 L) B
setcolor(getmaxcolor()); $ U) }# U; E6 d& `9 L
/* message in default full-screen viewport */
5 w/ P. n+ `3 _7 x4 j# A! Touttextxy(0, 0, "* <-- (0, 0) in default viewport"); 
; B+ D6 u' J" r1 ~3 B @7 K/* create a smaller viewport */ E8 w5 q5 P" B4 m
setviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON); 
+ U+ H, F- N7 Q% l/* display some text */ 3 m4 n' {# h# W& P9 r8 F3 \
outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 
; h! Z3 p! W% b" V/* clean up */
: T) m+ o w0 N' K" R' mgetch(); % C8 O, @7 p1 A v" o& P
closegraph();
+ t* @9 d! d- Ireturn 0; . @7 w* t$ j5 b: Z |" i
}
3 g( i0 R' r2 w' n9 d8 h g& i# `/ Y$ ]9 u

- z, \8 B: m" t2 C$ u函数名: setvisualpage c% _6 ?) K% \" F' M; x
功能: 设置可见图形页号
9 @5 ~; x6 }. X3 B' n用法: void far setvisualpage(int pagenum); $ g* l1 {( {- d* { w3 k
程序例: 
( a% B, v6 A% J7 B" i#include <GRAPHICS.H>: g/ o4 J) D4 y: v! L
#include <STDLIB.H>
" d. P7 Z& W' z2 d#include <STDIO.H>8 _# \! ]* F' M4 l& z
#include <CONIO.H>
- F8 u( `% R" ?+ ]0 K7 Gint main(void) 6 p# q9 g0 V0 P) [
{
; _% S$ g4 L G. E/* select a driver and mode that supports */
1 x( e& r- ?% Z$ m* ~& P9 } R: W/* multiple pages. */ 3 y7 D6 [* A5 C7 { e1 w; C
int gdriver = EGA, gmode = EGAHI, errorcode; 5 ~ J4 l" a6 x3 i% [2 T9 ^( z1 H' }( m
int x, y, ht; 
. W$ P F9 S ? x0 \/* initialize graphics and local variables */
; _8 @3 n# v6 h4 @- H- w: ninitgraph(&gdriver, &gmode, ""); & ]) E6 q) L( | G
/* read result of initialization */ 8 c8 A% C, T- r C
errorcode = graphresult();
6 j5 ?. Z a1 lif (errorcode != grOk) /* an error occurred */ / [( p+ O3 I+ b2 g& s% c$ |) m
{
$ L2 R5 @2 J1 z, aprintf("Graphics error: %s\n", grapherrormsg(errorcode)); " w7 F& Q1 Y0 `, p6 p
printf("Press any key to halt:"); ; D2 v6 G) u0 v8 s! K
getch(); $ m( H( P& r: i5 T5 s& u
exit(1); /* terminate with an error code */
$ D# s8 u7 G1 e( W} 0 v( y2 C9 S6 |& O" S( K. e
x = getmaxx() / 2;
( q W1 P" j E+ Xy = getmaxy() / 2;
 V; {* B# x$ _4 n- Wht = textheight("W"); 8 ]4 |/ z3 |$ ?) Q. Y2 i4 U i
/* select the off screen page for drawing */
, w3 V) H$ r) w* g- Csetactivepage(1); 
2 @/ B4 g, _' n$ b5 j" T, {( Y/* draw a line on page #1 */ ) M* U! r8 U& X" z, D1 D y
line(0, 0, getmaxx(), getmaxy()); 0 p8 I; M5 b# u
/* output a message on page #1 */
2 B" o- z- E1 b- ^! ^" @" L" Dsettextjustify(CENTER_TEXT, CENTER_TEXT);
" N. \! e+ Y. ?5 l6 Youttextxy(x, y, "This is page #1:");
4 m+ u% d5 d5 Qouttextxy(x, y+ht, "Press any key to halt:"); 6 ~% ^) u, l7 W6 p5 J6 {4 O
/* select drawing to page #0 */
) C* @" Z0 X7 c: y# ^$ U5 d5 ~: z2 Hsetactivepage(0); & L1 Q9 P+ m1 ]# A0 C
/* output a message on page #0 */
+ I$ P M$ X: q# Louttextxy(x, y, "This is page #0."); " @. O, T( D& X/ B T& \( h. A
outtextxy(x, y+ht, "Press any key to view page #1:"); 0 I) c {, t$ q& w
getch(); 0 k2 O; o6 O: v/ z: F1 S3 B
/* select page #1 as the visible page */
 s: @! p R7 Tsetvisualpage(1); 1 ^1 {* x* @1 Y4 q4 [/ o- V
/* clean up */ 1 S/ u; ]0 K* Q' I5 B$ f6 Q$ ?
getch();
# @1 m1 v2 k I- J! Q" ~+ Aclosegraph(); ) U. O4 Y- U* T1 x5 b/ s
return 0;
2 O0 H+ B3 g' U* }} ; y s4 X" `) Q- H6 D. p2 ?5 L" Z' M `

, V: o. y* y/ z6 A! V1 Y3 Z' n
& O/ Y' y8 B( X8 H) E函数名: setwritemode 
( E a! E, k* U9 H, E功能: 设置图形方式下画线的输出模式 2 N! p, z) f. v3 m
用法: void far setwritemode(int mode);
) M1 m @, j- z8 N O6 Q \程序例: ( P- v" f5 N2 i8 U8 {
#include <GRAPHICS.H>
$ [ J3 p5 e9 c#include <STDLIB.H>
7 Q5 U6 s9 v" I! {+ o3 {- n q#include <STDIO.H>0 e( i( ?5 j9 O ]8 z
#include <CONIO.H>6 c- d% A7 {3 U* Z/ i' W- e: z" N
int main() # o5 A) g3 S8 @
{ ! y5 a: M A- Q: j; ~* ?
/* request auto detection */
3 J0 [4 Q5 j3 t* Sint gdriver = DETECT, gmode, errorcode;
- J7 ]2 s5 E5 A9 E6 ]" @int xmax, ymax; ! P1 F0 p, A5 k2 B- \4 B
/* initialize graphics and local variables */ # [# N/ M# E( ~' D) g/ p3 c% S7 B
initgraph(&gdriver, &gmode, ""); 
4 p# H, X$ f, _( E1 a3 f+ M/* read result of initialization */ ( l5 S |% t7 _& R* s
errorcode = graphresult();
; D. C3 \: v1 G" z( Pif (errorcode != grOk) /* an error occurred */
* H6 U9 x7 h% b7 u2 H3 g{
4 p) y6 I3 B; U- F1 q. r/ Cprintf("Graphics error: %s\n", grapherrormsg(errorcode)); ! c/ o# o# C7 F- C9 Y: T
printf("Press any key to halt:");
- r3 U4 W8 e0 m0 r( E2 }getch(); 3 s$ _" E# @9 K9 b; n
exit(1); /* terminate with an error code */ 0 v5 y9 S* J, B8 `, \$ ~3 o! z
} 
/ c& W; E# z: {xmax = getmaxx();
- z* P' R" X4 ` s/ c' ?4 Gymax = getmaxy(); 
* f7 p9 g5 n" V7 t9 ]4 q3 M/* select XOR drawing mode */ 5 h1 N! |4 d' n L
setwritemode(XOR_PUT); 
0 O7 `9 b. ~4 z0 `1 |8 ?/* draw a line */
' Q) I: \* O- O; @ |line(0, 0, xmax, ymax); ! |* `3 r5 P, \ I5 f9 \+ U( K- {. {* ~
getch(); : e8 n; W) u1 B8 \
/* erase the line by drawing over it */ o2 J: [4 U; n5 ^, T0 M
line(0, 0, xmax, ymax);
+ c5 i- i5 Y, B( ~) Mgetch(); 7 T# F$ H5 w/ F% ^# S5 @5 F: h$ f
/* select overwrite drawing mode */ " a1 p; C0 w% |; ]
setwritemode(COPY_PUT); , `, o3 B# m; o$ `! q
/* draw a line */
3 N9 G4 n; ^. F$ b2 Z r1 g7 C7 [" Xline(0, 0, xmax, ymax); 8 | B- \4 w9 p# q2 B' T9 a
/* clean up */ " `7 ?, e+ g7 f5 F) Y, P: i1 k
getch(); . e+ t8 S+ }8 q; K) }" T4 c
closegraph();
# J& p& Q: [. {4 G& J2 yreturn 0; / N% u+ x: a, F* |# {# @
}
7 c( K4 M$ z" p% i/ ]% G" a9 |# B! N( u* X9 a) v

. b3 L+ r7 O5 H! t+ A函数名: signal
% P3 f$ F' c' @5 O8 Y' Q9 ~! V功能: 设置某一信号的对应动作
2 \, |3 S5 g* v) w9 `+ L用法: int signal(int sig, sigfun fname);
6 R8 c9 Y6 }2 \) o程序例: 
' K- h0 E7 f+ K/ E" U3 g/* This example installs a signal handler routine for SIGFPE, % F1 {- F' j( c" G$ X
catches an integer overflow condition, makes an adjustment # j0 Y2 P: v3 j, h% J( @: Z
to AX register, and returns. This example program MAY cause
' h' M7 ?8 j! L- v- Dyour computer to crash, and will produce runtime errors
/ [" D+ ^$ |* r3 r: I$ qdepending on which memory model is used.
! N; v# k; t/ Q; M- B* o*/ 9 Y1 {) O/ P3 N' ^
#pragma inline ; U# w. ]; z. E
#include <STDIO.H>+ N: m8 c. Q* w7 f6 E: i# l% F
#include <SIGNAL.H>
. h' s9 W p0 fvoid Catcher(int sig, int type, int *reglist)
. w/ C# g; o: P& l+ a{
& c* l8 {% _$ T/ E" ~' Yprintf("Caught it!\n");
" M8 ^# Y; f3 l* ]4 I( }+ ^- y3 T*(reglist + 8) = 3; /* make return AX = 3 */
5 y9 T9 G" p9 Z2 g} 
. n6 Y) _) O+ Y1 wint main(void)
* E; u! r. |# _4 g) d) m{ B7 p6 U; h% o
signal(SIGFPE, Catcher); ; K8 E( w2 M8 t( q; F. y. w- Y$ x8 ~
asm mov ax,07FFFH /* AX = 32767 */ & i4 n" g* b# b4 I4 k
asm inc ax /* cause overflow */
1 h- j4 B$ m9 M& a' h5 ?asm into /* activate handler */ / H* [2 \! |0 ?# K+ s5 @$ y. {6 O
/* The handler set AX to 3 on return. If that hadn't happened, 7 Z' q. }; f3 c6 K) m7 S
there would have been another exception when the next 'into'
! G( ?9 _: B1 nwas executed after the 'dec' instruction. */
" a( Y4 z/ d- i2 Casm dec ax /* no overflow now */ % p" H1 I8 i/ z* F& j" [
asm into /* doesn't activate */ 3 g& _* d# |4 a" V" }2 ?
return 0;
2 Q3 c2 E, |6 N8 s( G}
( D( H, L2 J$ u* m! j+ j$ J: `
" `' f- h. u. E- B( {* ?
. v& s, A/ C q' ]7 H! E/ R
' R: n, a, Y% X5 t; V# e& \函数名: sin 
4 E5 A. ^8 v( W7 K0 B/ y4 }3 |功能: 正弦函数 " ~: L$ C, z% Z$ w
用法: double sin(double x);
* O: T9 s8 ^/ S; [( \/ }8 Z程序例: 
8 _4 F4 l2 b% W" P r) f0 \#include <STDIO.H>7 Q; y Y; Q. f0 |+ `- S: T
#include <MATH.H>
; t: v/ \, e7 Zint main(void)
4 h3 ]0 }$ B7 ?; \, R: W% d9 @{ : ~1 S* g( k. ]/ O& }3 q& _! b
double result, x = 0.5; 
. B4 d: e% s% t. Y- d4 d( `result = sin(x); ; K, e- ?9 p4 h/ s N
printf("The sin() of %lf is %lf\n", x, result);
9 b2 B6 n4 m/ c& S. {, Z3 \return 0;
7 L: U. d" f& T7 b} & B+ P( h8 U8 k x D) N+ ]( H: K
1 P; E4 X6 \( f* T$ g

% ], h u% V, c( a+ E- d" q5 f0 A函数名: sinh 
; s5 R6 o/ I# @, X" q功能: 双曲正弦函数
+ s Q$ {% s# V用法: double sinh(double x);
1 j+ ` I# r, o$ _. h2 {+ w2 N程序例: 4 |5 N4 U+ X" _ }
#include <STDIO.H>
6 S. g& y1 }8 D; {#include <MATH.H>4 K: o2 S& e( g; o0 Y, Y* E' S
int main(void)
4 T& _6 N1 m& z& [{
$ Q6 b v: L4 H5 W9 E. Odouble result, x = 0.5; 
" f1 j8 r0 _1 P) Wresult = sinh(x);
- N4 X( {: x; ~5 {, oprintf("The hyperbolic sin() of %lf is %lf\n", x, result); - C, x2 r9 ~3 t% Z. r
return 0; * J3 i( L7 J+ ~. C
}
: y ]) U* q' m/ Z% h" a, X2 O. r
8 t o+ J9 N9 `0 a0 m: q; O6 a1 F6 Q) ^

9 E* ]6 R# A6 y) u4 [2 c函数名: sleep 
, k9 E, u2 k7 n; t8 |6 x功能: 执行挂起一段时间 + q$ T0 x5 B' A) e# c, S1 J
用法: unsigned sleep(unsigned seconds); * T3 E4 G! v$ q* D/ E
程序例: 
. B0 O2 e+ C; y% ?4 U7 x' F) U$ Y#include <DOS.H>
7 v8 u3 L& P, l#include <STDIO.H>
- M% x: R c6 c& \9 ~4 iint main(void) 7 |3 a3 r& w- ?9 X6 [+ r0 l
{ + E" \. K! I: R1 T/ p3 W
int i; 9 T# Q0 `* ~/ n3 i8 q" G
for (i=1; i<5; i++)
: u5 Y/ J2 Y F. L+ d6 |8 ~{ * z0 O/ D6 U4 c0 L! W. ~
printf("Sleeping for %d seconds\n", i); 1 ?% O% `. C! I* W% Z
sleep(i); - b w% U' @, N) g
}
' k6 H+ T0 t3 @return 0; % l+ [* i3 x# }. e( A! D t
} # w- [3 V! [3 I* |# O

- o- W& x5 `- W) k/ B
, q. l5 h; c J0 N. ?: D' n
- s: v8 T0 ?, \7 e5 ?函数名: sopen . j3 n% b0 b( B G
功能: 打开一共享文件
" p# k# ^4 ^- q m; A) i7 X用法: int sopen(char *pathname, int access, int shflag, int permiss); s* `' K5 q* f, Y3 L* B
程序例: , T" |, E) W8 Y1 `3 ~6 B R
#include <IO.H>; O# z v! P: L8 Y
#include <FCNTL.H>, M6 E, f5 a3 r+ n# t1 S7 l( C! S
#include <SYS\STAT.H>
 s1 F3 v U9 A. B#include <PROCESS.H>; f8 L# D6 t* [- y: c; y
#include <SHARE.H>+ f- x+ [. t) f' R
#include <STDIO.H> t2 e( U2 q. v! t& i/ R5 v% O
int main(void) 2 C q& p% l. v1 D1 U1 U0 ?0 }
{
# z) p9 h8 C" pint handle;
3 c* y9 E( p8 t; vint status; ! F) H2 m" K! c1 F! t1 l
handle = sopen("c:\\autoexec.bat", O_RDONLY, SH_DENYNO, S_IREAD); 8 F! ~6 o) n6 f6 U% Y) Q# k" x
if (!handle)
$ i, @" P- x) U, S) c& O0 D) _{ # l' t1 _6 u8 _( [+ t6 _0 j5 q
printf("sopen failed\n");
2 M8 I, o8 Q* W. g5 n3 sexit(1);
9 t3 ?5 ^' }& x F9 z} 
6 A* V$ F: x! f q. m g3 Tstatus = access("c:\\autoexec.bat", 6);
" ~+ n2 F4 w: [% \* M7 |if (status == 0)
( ~" j1 z/ O9 _2 d3 l) x9 }printf("read/write access allowed\n");
$ F( L7 q' @0 \" d" P& b, zelse
+ H% f0 z. p! O4 M! [+ u) n9 bprintf("read/write access not allowed\n"); 0 z2 E& L& X" @4 C
close(handle); # X( N2 K/ A+ ^9 G+ v
return 0;
+ {2 a! R2 _2 Q3 c! s* j e}
( K6 T" M# C9 U" b1 r, b
+ y( {% V5 w8 E. D% X3 L0 G$ {1 u! ]$ q
9 Z6 O2 m% U7 L% J2 r
函数名: sound 
3 P* E- h+ ^7 X: F6 f功能: 以指定频率打开PC扬声器
" V- E. ~1 N2 X8 e用法: void sound(unsigned frequency);
3 ~6 B4 E8 ?5 r+ P7 Q! v程序例: 
7 u% l8 Z+ x9 t/ m( s/* Emits a 7-Hz tone for 10 seconds. % Q# a, O/ o i w2 G0 N- w
Your PC may not be able to emit a 7-Hz tone. */
#include <DOS.H>
# y. X6 ~9 f2 W, j% t, i# Y) E7 Z; eint main(void)
/ d- w) s& c0 m+ d p: I{ 1 E+ l+ A0 ?$ }# P2 S( x, s+ I! X9 N4 v
sound(7);
/ P- I* c' Y. {/ A% {/ Tdelay(10000); " v7 ^4 Y, i! N/ k2 s. L
nosound(); 8 |! j0 S# f9 Y, O: v- Y& Q9 @
return 0; + f E. T# f8 [* m
} 
- R2 m$ ?" W, }- `& s
( j6 e4 N) v! V' D$ ]7 h6 T$ v7 d; \( Y) G

" |% ]( U/ L0 ?, q4 C" T函数名: spawnl 
/ ^: @& a0 R8 d$ a k, I) U/ r功能: 创建并运行子程序
8 I7 @5 n9 f2 F! P2 P: O# a用法: int spawnl(int mode, char *pathname, char *arg0,
3 x; s' w: o% T' Larg1, ... argn, NULL);
* c; H N& g! V+ v) h6 r' h程序例: ) ]6 d" U7 D5 K3 @4 [- M7 v# u
#include <PROCESS.H>8 q1 V4 a% C3 q& h
#include <STDIO.H>: g* ^. N9 C5 B. x
#include <CONIO.H>5 R9 }4 Y1 `6 }
int main(void) $ L' m+ t* Z( G5 _
{ 1 p, O' E- L# F2 x& p* s3 W
int result; 
$ a% [( N {$ Aclrscr();
( T( V' P0 ]; |8 p* [/ F: k2 Vresult = spawnl(P_WAIT, "tcc.exe", NULL);
" E6 ~5 [8 [( A& }# ] c) Hif (result == -1)
: w: P8 D( K e4 g. C8 V{
; O% r( O z$ a% U7 f. \* Cperror("Error from spawnl"); : u8 _4 j5 `6 z6 [6 @& B
exit(1); 6 Y* s, r6 W4 @+ P; U
} ) |! Y, z2 `' d5 L4 h' H# @
return 0;
* Y- D _# I' ~- h# s}
: ~! ]0 v; _9 g! `& {! Z
: W. X- j- K0 L' j: \9 _! E/ ?0 T, K# a
函数名: spawnle , S( s4 Z+ k' e: d! | {. r0 z
功能: 创建并运行子程序
/ T9 j( _% M9 w; J0 F; b" e1 _用法: int spawnle(int mode, char *pathname, char *arg0, . ?- A/ t, E3 s/ u2 u
arg1,..., argn, NULL); 2 ~6 ]* K2 b1 G
程序例: 
" R9 o! ^7 e6 v8 a$ u9 j4 M/* spawnle() example */ " `/ r, C- V" {' J& z) Y$ V
#include <PROCESS.H>
. J% E( f, _6 w" s+ N8 ]#include <STDIO.H>
( B# n& P$ A* M5 }; e3 g#include <CONIO.H>8 b9 ^& Y& e8 x% b( `
int main(void)
6 X+ Q- E5 `4 r+ T; V{
0 [' B1 u, t" u/ Zint result; 0 o: J8 e: M! |: D
clrscr(); % Z0 y3 y* u: d9 C! E
result = spawnle(P_WAIT, "tcc.exe", NULL, NULL);
) P6 L8 ^1 w+ O% g/ kif (result == -1) & t L3 g6 g9 v6 f, {# X) U
{ ; {% V, q; Z+ l5 r: K! s3 T
perror("Error from spawnle");
# W0 P7 E9 M0 I6 {4 Cexit(1);
( V; {& e& S4 G$ _}
3 o' v3 v8 B. T7 Rreturn 0; ' G- R+ q, H9 N" h1 O4 h0 K+ e! N
} ' Y+ v7 C2 m/ Z7 ]; _9 f0 J
# u: w8 P$ y7 K, b7 ?

" x% d% t& J0 n' H' D/ Z2 u8 O, A. }0 S. N
函数名: sprintf 
" `. z% x& S2 ?4 @2 \功能: 送格式化输出到字符串中
: x5 G" l) n v: U8 n$ R用法: int sprintf(char *string, char *farmat [,argument,...]);
# j8 P; |" o0 H程序例: 4 x* H/ W" U# }1 [0 ?
#include <STDIO.H>7 L# o3 g- G/ {1 K. K* B9 t6 _
#include <MATH.H>
. J! e* C a5 |int main(void) / ?: l7 O( f6 d g- ^5 d8 H3 W
{
 {3 h7 d/ ]# T* z. H W4 u: w5 bchar buffer[80]; 4 r, e. b" f" z7 \3 u5 N$ E4 H8 w+ k
sprintf(buffer, "An approximation of Pi is %f\n", M_PI); 8 E! [/ \6 H2 J( L2 w+ I& O
puts(buffer); ; {; O. |5 w2 o: ]- t: o! `
return 0; ! W5 T- n( u9 E& J; p) W: w
} + L# @0 L7 Y, e! x
2 u/ H; ]6 N- q- h
0 R' ?, T/ o6 T7 d9 w
函数名: sqrt 
- y/ S4 S6 E) j1 S' O功能: 计算平方根 , J) e% E8 H2 G% a
用法: double sqrt(double x);
( d2 c& {9 P a+ R; s程序例: 
# m" I: ~5 O" l% J/ }% |5 @#include <MATH.H>7 E9 N/ N4 z+ `1 Y0 X
#include <STDIO.H> C5 G( y" }5 g7 n" X1 s2 u5 ^
int main(void) % i7 K: X' z0 N
{ 9 D# `% R+ s3 E! S2 ^8 S5 j0 B# `
double x = 4.0, result; 2 I4 k+ p) [5 [
result = sqrt(x); $ K1 `2 N) [: C4 }$ b
printf("The square root of %lf is %lf\n", x, result); . j! B6 y4 Z. [) P' c9 b. R3 r! [
return 0;
. n y5 V! p5 h$ [} . t& \: T- [3 {% [
3 R, o$ B* l( m: ` U
函数名: srand {' A& N) p+ v
功能: 初始化随机数发生器 6 c# j1 d8 m$ S' A
用法: void srand(unsigned seed);
" t3 s6 h& c/ e9 M! y. [* W) J E程序例: 
- P1 V1 _! N% q/ l8 S; E& l X#include <STDLIB.H>
( U) B- |! l! R+ v#include <STDIO.H>- k! {4 n h7 [7 }# O2 y2 u
#include <TIME.H>
% X m2 H+ G0 h& i _4 rint main(void) - j- I# ~- X$ B8 D- a
{
 |# _9 } \5 g* cint i;
, Y) ~: b& u# @time_t t; . F+ Z% I. D* X" e9 k0 D
srand((unsigned) time(&t)); . i$ N3 }) |" N' ]3 [6 E) |" F( `
printf("Ten random numbers from 0 to 99\n\n"); 3 I$ z7 J* x! `* r; ]; b
for(i=0; i<10; i++) 5 Y1 r0 ^/ d) n! `1 Y9 c% \/ g& }
printf("%d\n", rand() % 100); 1 n( C* h6 ] a7 Z
return 0; 0 f) w- ]$ ?- { |1 ^6 ]" R3 g
}
* r8 v+ b/ v7 E9 M! J) @( j( a6 X

, U: p5 f' N% A$ X" C: d函数名: sscanf ; s( b: M1 i4 m5 w2 }" ~/ H( Y9 D% W6 p
功能: 执行从字符串中的格式化输入 : m" ?, G0 h, X( N; g8 j
用法: int sscanf(char *string, char *format[,argument,...]); ! P) [- y9 `, j* `$ Y/ U' w
程序例: # V1 _$ b3 J- G6 n) e+ j& P
#include <STDIO.H>
$ h8 v; F& ^7 D7 m/ `- n$ E#include <CONIO.H>1 L" p6 J% s A3 Z
int main(void) 0 ]- T8 V$ R# L' o( ?1 w) z
{ f2 I% @# v }% ?
char label[20]; , C/ w# H' \8 X. T% w: W o
char name[20]; & |. D$ C0 }+ c2 N/ q" ^1 W
int entries = 0;
8 Q! L9 j3 X9 U! ^0 ~int loop, age; / |, E6 ~3 w) }. I6 Y3 `
double salary; % U* @+ L# A5 I4 C, `( l
struct Entry_struct
& w& e, F' a7 `{
" d- ?1 C2 }1 Qchar name[20];
, ^! o# d ]9 }. {8 s# Tint age;
' _7 m. ^5 o* `0 X% ~float salary; ( z1 Y4 P3 O3 k4 X7 S) J
} entry[20]; 
9 j& `7 u9 ?8 O9 Q3 j/* Input a label as a string of characters restricting to 20 characters */
5 U; c8 C9 z/ F D" S% Nprintf("\n\nPlease enter a label for the chart: "); ! f% }9 g9 _& c1 h; {$ L! L
scanf("%20s", label);
8 c( Z* n3 b# p# Sfflush(stdin); /* flush the input stream in case of bad input */ 4 [0 P. Q3 H- c& r" a1 y
/* Input number of entries as an integer */ - a3 M! d6 L& p- H$ I, v
printf("How many entries will there be? (less than 20) "); ) L/ ?: E a4 y8 F5 d0 [
scanf("%d", &entries);
7 D4 M1 f/ C; ^$ l4 mfflush(stdin); /* flush the input stream in case of bad input */ 
0 k" ]/ S+ k3 J' O/* input a name restricting input to only letters upper or lower case */ * C+ z0 `, n6 ?! W, s0 Y! F* I1 f
for (loop=0;loop<ENTRIES;++LOOP)
3 p/ a' N) Y% S/ M { ! ^: ?$ s8 f, p
printf("Entry %d\n", loop); 4 V' ^" \' r- e* U+ @1 ]! b6 w7 B
printf(" Name : ");
) D1 j3 U T2 m# Rscanf("%[A-Za-z]", entry[loop].name); * v( T0 Y z$ S6 I$ ~
fflush(stdin); /* flush the input stream in case of bad input */ / j( w! r+ ]/ z! ]( N
/* input an age as an integer */ 7 w5 J2 X. z5 H7 X5 \, l1 D- m. R
printf(" Age : ");
$ j6 N) f" p3 N3 p4 {& a, B7 Fscanf("%d", &entry[loop].age); 0 @' I$ I- b# X7 r b' j' ]
fflush(stdin); /* flush the input stream in case of bad input */ 8 a$ X% ^9 Y. T. i! I7 r
/* input a salary as a float */
1 w/ w' l! n8 | H( H uprintf(" Salary : "); ' n5 t4 L. Y: Q$ W% l/ R
scanf("%f", &entry[loop].salary);
* o. h) w3 t. h/ L* B8 F% Z- W9 xfflush(stdin); /* flush the input stream in case of bad input */
& C; W- x g F- D8 P} + C8 |/ |( s& [) @
/* Input a name, age and salary as a string, integer, and double */
3 o. Y& S& a: _4 s6 mprintf("\nPlease enter your name, age and salary\n");
' w2 O1 T, T6 {4 b, D4 Rscanf("%20s %d %lf", name, &age, &salary); 3 P6 g$ b7 B `/ D' D3 a( m

0 j& E; I4 _$ y2 S! c/* Print out the data that was input */
. j n; c) B. @8 {/ v* Xprintf("\n\nTable %s\n",label); & e. K4 V# Q; O
printf("Compiled by %s age %d $%15.2lf\n", name, age, salary); 1 N# c" |' G$ |+ W& g2 s& `7 j
printf("-----------------------------------------------------\n"); ' l' w3 `2 ]( K* y: j. }6 M1 x% {
for (loop=0;loop<ENTRIES;++LOOP) % X& \+ T+ T7 t" X
printf("%4d | %-20s | %5d | %15.2lf\n",
7 |/ w s L$ }( H X2 Qloop + 1, ; {7 T% Q D3 I
entry[loop].name,
) z0 z" t' c( P4 B* G4 Z) kentry[loop].age, . c4 w$ e! S8 z- l4 K1 {% I
entry[loop].salary);
/ l0 _* B3 {9 U4 N5 ^, gprintf("-----------------------------------------------------\n"); 3 [8 T* i$ o" Q2 `2 q
return 0; , w0 P3 m* j9 C, y9 j& P
}
: E# L* z1 \" y" h
; x; [4 }+ w8 q) b0 a- J" b5 v2 }& e6 @
函数名: stat # V" I; z2 U/ M8 i/ [
功能: 读取打开文件信息
 t" x" I x* {5 D: P9 O4 |& @用法: int stat(char *pathname, struct stat *buff);
( K: A" ^8 q0 B* j E程序例: 2 z0 Q0 ?3 i- I9 D, R) Q" J# o; ~
#include <SYS\STAT.H>+ n' y( h4 `/ u$ C8 {5 e3 k/ P
#include <STDIO.H>
+ I8 c& L! I' M4 |3 p) I/ `; Y% g#include <TIME.H>
+ g; b# o$ H+ g- z4 ~" o#define FILENAME "TEST.$$$" 
; h# e g; x3 ?# U& [# Wint main(void)
 r* M# ^/ \4 c( C& ]& _{ 0 @- Q% f" H, v5 D% w
struct stat statbuf;
/ i, a# S; ^4 t1 c7 W5 rFILE *stream; 
. J: H" S$ x/ s/* open a file for update */ , G' c' I4 V4 ]
if ((stream = fopen(FILENAME, "w+")) == NULL)
6 ~2 ^: D( z; {9 f9 ?{ 1 Q6 b. m% Y9 V8 U5 ], O2 v
fprintf(stderr, "Cannot open output file.\n"); 5 `- t% \1 U$ V( n" X* S* @# W' C
return(1); & ~+ _# v9 u. T! q* X D
} 
* h8 M) u& S& c, `% j/* get information about the file */
) O2 b$ q* F9 B8 ?8 ystat(FILENAME, &statbuf); 
$ }/ C/ H! {3 L. Z: Yfclose(stream); 4 K: e2 ]9 x6 y
/* display the information returned */
2 i/ j& u: ?3 l6 B* V! N) G, W1 H& h1 Lif (statbuf.st_mode & S_IFCHR) 7 o2 |( l* V+ f' J4 k; C' r: x
printf("Handle refers to a device.\n");
8 G( [; Q" X! i1 Lif (statbuf.st_mode & S_IFREG) ]$ z4 S% j" I' M
printf("Handle refers to an ordinary file.\n"); 3 a; K, E* v) g `/ L. J/ R
if (statbuf.st_mode & S_IREAD) 4 H' U1 @: h# F
printf("User has read permission on file.\n");
4 Z U: F/ | M3 [5 bif (statbuf.st_mode & S_IWRITE) ) V* G9 D5 |1 o0 ?( ?
printf("User has write permission on file.\n"); 
6 H8 ]; @! V' @2 S. Dprintf("Drive letter of file: %c\n", 'A'+statbuf.st_dev);
; j3 ]$ w# W0 N9 ]% D9 kprintf("Size of file in bytes: %ld\n", statbuf.st_size); - V+ q$ h* N# q/ S! n
printf("Time file last opened: %s\n", ctime(&statbuf.st_ctime));
+ |& w3 A" c/ Zreturn 0; 0 q K! o: c# I; O3 W. P
}
7 Z, k2 L) v4 k1 r
, G; H3 o, d2 O3 _! n5 P, f: Q+ x6 Z) g; j$ V. O' G

8 ~* v, t3 p" T; @# Q函数名: _status87 c& a6 b% V, j* k3 z
功能: 取浮点状态 " x& f% _* l; K y" k# T. j( ~
用法: unsigned int _status87(void);
! C2 i g4 ~1 r" a& ~程序例: 
5 R8 z# L2 ^5 E: q" J! ~#include <STDIO.H>
6 ?5 p2 I" y) L& N) V5 k2 h#include <FLOAT.H>
- t. o4 X6 q) L5 z; Nint main(void)
+ ?$ M6 r f& U& {1 R{ - ?, c% A3 C1 w: j8 n6 r) Q, C
float x; * _- a# Z- q4 W
double y = 1.5e-100; + X* T% w+ h) `9 R; K6 r
printf("Status 87 before error: %x\n", _status87()); $ F. c' E$ E. W+ O
x = y; /* <-- force an error to occur */ # Y+ S' d- N! ]) U5 A# m1 p9 M- _0 ]1 x
y = x; 
# }( x3 ?. f; d3 `* I# R Kprintf("Status 87 after error : %x\n", _status87()); 9 }( m& w, O! B! n( M( H
return 0; u5 Y2 O4 {. `4 e! V9 O- S
}
( P5 W. ]. g8 P% O- U5 |8 ~/ w l" \6 o

( Z( L: }4 L* |! ~6 `6 [8 P- P, J函数名: stime 4 K# `5 R$ l5 L* @8 ^
功能: 设置时间 5 ^( c* x6 p7 |. v
用法: int stime(long *tp);
7 S% E6 o2 }4 s程序例: 
3 b: e5 g" H9 a- }" N! @# M#include <STDIO.H>% d! m6 G4 o4 f# }$ ?
#include <TIME.H>! {. b9 _8 T8 T2 F1 ~
#include <DOS.H> X* P F! X2 }* ]
int main(void)
0 W1 b& l( p5 E' f{ 1 r7 i0 g6 c# Q M6 ]4 a& ]( P0 L
time_t t; ( S5 h6 N& y; W6 y e7 d
struct tm *area; + K4 m: p- j% m4 ]5 W# x2 Q
t = time(NULL);
3 [ \1 c( {; J8 j4 H- Harea = localtime(&t);
! i6 _% g4 I7 Fprintf("Number of seconds since 1/1/1970 is: %ld\n", t);
1 q" j% V9 a* r1 mprintf("Local time is: %s", asctime(area)); 
. t+ a2 k; q* }$ d" St++;
4 k9 N3 ^' Q/ r. D0 x" \" x9 \area = localtime(&t); 9 }! G* C( W5 B: E
printf("Add a second: %s", asctime(area)); . J6 O; H6 p ^! D6 U6 J7 G
t += 60; , K' {8 V/ g( \
area = localtime(&t); 7 k1 O! \0 I8 G2 B
printf("Add a minute: %s", asctime(area)); 
2 Y- J! A2 E3 s# Ft += 3600;
- g; }( H8 `3 F. B4 larea = localtime(&t); ) ]- r2 H5 u- K/ t, Q- V2 R
printf("Add an hour: %s", asctime(area)); H% }0 |7 R2 @6 C$ n2 } k! t8 _! w. l
t += 86400L;
+ G" r V' F) s0 g+ {area = localtime(&t); : P% Q/ ~ _( I V; x
printf("Add a day: %s", asctime(area)); 
0 ^ q4 y8 F/ @: w9 T9 _( ]t += 2592000L; ; M; W. {$ t* c! l! S1 B9 y( |
area = localtime(&t); ! h0 R8 v. @5 |/ v, r- o* t
printf("Add a month: %s", asctime(area)); 
! V2 i4 P3 Y3 ?7 w% zt += 31536000L;
( `9 \. a( E: S4 p! {( G* Warea = localtime(&t); ' M3 |/ z7 {2 g& W3 N, C9 ]2 i3 C
printf("Add a year: %s", asctime(area));
1 G0 j) n6 ]4 w# [- l8 E4 yreturn 0; # c0 ~9 b4 a2 T
} 9 ~5 e: y. [/ Q" \

# w; Q. L" N- K+ N9 D& t% h! V& u1 p8 V8 ~0 A

9 O4 `! I" G4 F* Z3 Y+ B6 P函数名: stpcpy 
$ R3 y i4 C& y6 r* @功能: 拷贝一个字符串到另一个
7 N/ n/ Z; a" {$ R. P8 Z# H用法: char *stpcpy(char *destin, char *source); T, y7 i$ F; ~
程序例: 
8 o! [% I$ w. ]: _2 w+ f, c#include <STDIO.H>
$ w+ A. z0 S( G( i% M#include <STRING.H>
3 k0 m+ J6 Y1 S6 u. n6 P# `8 xint main(void) % d% H) ?3 A$ b* }+ Z4 l1 l
{
/ v$ m1 R9 l! _ \( Bchar string[10]; 5 O+ W! {" y8 f1 m8 [
char *str1 = "abcdefghi"; 
8 V3 K$ ^- g$ E; nstpcpy(string, str1);
0 W% e8 G( B3 m- c) I1 M, J& a/ eprintf("%s\n", string); 4 n4 |; C# a) s# h
return 0; + v4 @9 ?% ]. W- u
} 5 T; x/ D& Q/ }5 f* ?, |

- w& t7 e$ _9 n! i+ N& a8 l7 N
% k: R1 n/ o+ T0 D% a6 {; b4 |7 y
+ b- `3 U% W1 j+ x7 `; o2 o/ q函数名: strcat 
1 v3 U% I, v$ `/ e# Z+ R' B功能: 字符串拼接函数
) J, l5 V, G6 J' `用法: char *strcat(char *destin, char *source);
0 S/ B, h" |7 g: o程序例: 
2 I# l, b2 v* b2 |7 K/ {! o! ]#include <STRING.H>2 i4 {8 n* I# s; L; b1 p7 G
#include <STDIO.H>7 ?1 m4 b* `6 y# c* D* x
int main(void) 1 Q: f& {& S y/ P) }
{ $ m3 J" {1 m( e
char destination[25];
7 C7 r4 ~- C8 N+ B/ x- j$ i2 `char *blank = " ", *c = "C++", *Borland = "Borland"; - H) b' y* K, Q# ?) u% ^# A
strcpy(destination, Borland); 6 p$ U$ A6 G- z3 S* W5 }, x, t/ t
strcat(destination, blank);
 G6 z5 B$ F9 a" R7 B, `strcat(destination, c); 3 n1 o, F+ d) y
printf("%s\n", destination);
0 ?" u: @) }1 b* u/ n2 dreturn 0;
& V: h; o2 f% x( y; ?; x} % C4 T" f$ A G8 X9 N! @
6 r5 A3 `5 K7 S0 d# l2 i4 @

5 j/ `# q" I8 P! q: ~
3 s9 b# |. Z+ i% B/ V. l# R3 \函数名: strchr 
# D" h; V/ |& }8 \- p+ w( e功能: 在一个串中查找给定字符的第一个匹配之处\
- f2 T( m& A& R, i用法: char *strchr(char *str, char c); 6 J" v6 _' f( }" Z) G! S
程序例: + i2 T( D; y( G' m+ X+ N4 c+ h
#include <STRING.H>
2 S' |# g- n' W3 N#include <STDIO.H>, s2 _$ D% r6 E/ z6 q$ V
int main(void) - b5 n- h' O# h% B( V b# W" }
{
$ q; u, P, ~# \& c4 l& _char string[15]; $ j8 P9 b6 L3 T6 J; l n! A7 o% f7 A
char *ptr, c = 'r'; ! Q! R7 _; @ |0 H
strcpy(string, "This is a string");
- Q u' {& U5 L+ rptr = strchr(string, c); ( P; t4 F C. C2 w. j3 h
if (ptr)
2 f- A: n0 b- U4 t5 Cprintf("The character %c is at position: %d\n", c, ptr-string); 0 g- z+ O" {% T' {
else 0 o6 F$ G) k) Q
printf("The character was not found\n");
# f) O) q, T3 S& [6 K, ireturn 0;
/ G) [' p v! Z8 u$ x. w& n} 9 X- I4 P" F+ B2 k h" n

3 \9 b. d: K7 i1 K# e% F& J& p4 N2 B: [* s4 x3 g3 V

0 w' N) ^3 U' [5 q$ a4 c5 H函数名: strcmp
) m0 S& n& M/ v6 d- l1 X( R功能: 串比较
4 Z4 z0 R: o1 B8 h用法: int strcmp(char *str1, char *str2);
0 k1 w* k. v$ f" y* C2 N) Y程序例: 
, |5 y0 }/ g" d: y( ?8 H#include <STRING.H>
% R. y5 h/ f4 t" O* g" ^! M1 u: M#include <STDIO.H>
) |3 P8 t1 _- C; C( J# Vint main(void) . [& M( ]; o6 k; l& q# P$ i
{ / ?$ _/ a: D1 L/ O
char *buf1 = "aaa", *buf2 = "bbb", *buf3 = "ccc";
: D% d& I7 m: F) Fint ptr; 
- Y" [! N+ o9 k' ?! ~8 m l" I8 ~; ?ptr = strcmp(buf2, buf1); ) f+ S/ l: I- K6 M3 k; |
if (ptr > 0) 9 e+ S. r/ r8 t; Q) s+ V: C
printf("buffer 2 is greater than buffer 1\n"); 3 h3 c$ e) j) N
else
' b" U/ h0 g; | n1 B( k% Kprintf("buffer 2 is less than buffer 1\n"); 
- U9 ` |: i1 G* Optr = strcmp(buf2, buf3);
- V/ j5 m! a* f" ~if (ptr > 0) - M' G* e4 l" T% C5 X5 `
printf("buffer 2 is greater than buffer 3\n"); , F$ y+ u8 O4 [. H
else " i* O: k+ l, p" y. ]
printf("buffer 2 is less than buffer 3\n"); 
1 K2 w3 Y, r8 i7 A$ k7 d3 `return 0;
0 X0 X# s: z5 o3 b/ P+ X" i X8 ~0 R} 0 I; [: B. U# {+ J! E2 X5 D

( M2 Q) l! d7 @9 R$ p# H- _2 v. n/ p! w9 l

! y3 ~1 q. z+ N- u+ Z函数名: strncmpi 
2 D9 ?8 v$ G- A$ f2 a功能: 将一个串中的一部分与另一个串比较, 不管大小写
 @* t' v8 T. |4 @1 C# R; E: T用法: int strncmpi(char *str1, char *str2, unsigned maxlen);
! S3 t$ ^5 d7 f* ?" D5 v- x( F& v程序例: - r" @) s- B$ h3 [/ I
#include <STRING.H>
! Q( F, |1 T4 r% W2 f( _4 W#include <STDIO.H>" q& c0 p! W2 e9 x1 O
int main(void) 5 p9 M! S. S5 u3 V
{
3 k- N& i7 `8 F+ f! Q; xchar *buf1 = "BBB", *buf2 = "bbb"; . r; l* J! h8 s9 `+ }7 r* c
int ptr; 
& F2 r3 W' k" a2 M2 Jptr = strcmpi(buf2, buf1); ; ~- M4 Q+ r2 Z' P7 P7 K& B
if (ptr > 0) 9 M. n8 J( C' x; H6 ^& ^2 }
printf("buffer 2 is greater than buffer 1\n"); 
) R5 z2 O& ?4 j. kif (ptr < 0) ! h8 s0 t4 q( O- M) R
printf("buffer 2 is less than buffer 1\n"); 
5 { A; b9 F9 d5 n6 lif (ptr == 0)
8 h: J$ c6 ?3 f. t" Rprintf("buffer 2 equals buffer 1\n"); 8 I5 Q: r% D Y
return 0; 4 E1 W" t# D& |2 V( z9 ~' {
} + x8 u p: R: Q$ }: G: g: s

" u" E3 f) y+ b* a5 S8 p- w c( Y8 ]7 w; M- q1 J9 I
) Z' D$ z8 t! v; o" c3 _* j) X
函数名: strcpy : K. C9 f; F) Q9 I
功能: 串拷贝 . O0 ~9 I. m! P& {/ H [
用法: char *strcpy(char *str1, char *str2);
2 Z! A9 _" e! F程序例: 1 n& s) G2 {4 z# \
#include <STDIO.H>
/ a: A9 J) {. |& G( q8 B( E8 u#include <STRING.H>, ^; W7 r5 F; {& S6 e5 I6 E
int main(void) * v; T4 c' W* d0 V5 G1 F6 o1 J. Z( ?
{
( \8 t& d2 Y, M# tchar string[10]; $ w2 t" U- T" {, i- K% P% w% J
char *str1 = "abcdefghi"; 
/ Q: ~5 b g8 ]% i+ k" i& tstrcpy(string, str1);
7 ]8 v$ I" `6 j6 Q$ r* Sprintf("%s\n", string); : \ J; z# Y+ x7 |8 X2 U8 N
return 0;
, ~5 A. ~- o0 F7 D1 ^: p; A} + }4 w% \4 t7 V6 O' c( I5 l% {/ Z$ V4 C

) K9 n+ J8 i$ e% }( @7 l1 L* D
! q- P4 b. T) w, E# E* t. f. A& [/ k: w
函数名: strcspn 
6 u* t$ g( l! S6 e. N5 A功能: 在串中查找第一个给定字符集内容的段
7 c0 }. y( W# w4 {" n2 [/ r用法: int strcspn(char *str1, char *str2);
9 c& U* }8 u$ T4 u8 J程序例: 
% g( }; D/ ~% Y$ c* A+ F4 n* a#include <STDIO.H>8 \% d9 I) K/ N6 D# ^- L
#include <STRING.H>
! X7 T& s+ D& u9 Q0 ]: x#include <ALLOC.H>
! W5 g$ h0 h- s ]" t2 m3 ~int main(void)
. T7 t3 h; A" k{
1 s# S- c4 n1 Z' ?char *string1 = "1234567890"; 0 h! X& a+ n" C9 N4 v6 v
char *string2 = "747DC8";
8 t L% a5 ^& [1 K/ J0 Sint length; + ]' @7 I! A2 |+ p# U
length = strcspn(string1, string2); " Q0 S% }* r8 t6 p
printf("Character where strings intersect is at position %d\n", length); 
( z5 f* t, G, Z8 t8 f R; Kreturn 0; ; z0 W7 Y2 L* p& N4 S$ ^6 Z9 ?
}
% I" l" b8 N; k- |4 x" x5 S
9 M8 l! \# }3 t* P3 q( }5 C+ }+ e2 D/ X8 c6 {) S3 D9 U
" g, H' j1 _- I3 z2 k K2 |/ |& x
函数名: strdup ' m9 e, X, m; L2 y P! m2 }- x
功能: 将串拷贝到新建的位置处 . _$ z Y& ^! ]
用法: char *strdup(char *str);
3 u" J: g& _! l程序例: " O5 Q7 G: t- Y0 l' _( G" B
#include <STDIO.H>
3 v, V, G6 ^2 r7 E. w+ ^#include <STRING.H>
5 D0 U" q$ C! t#include <ALLOC.H>4 V8 Y. o) N" `0 S4 b
int main(void) : m" {8 N7 z. H3 N
{
9 M+ Z) D) n& x; Lchar *dup_str, *string = "abcde"; 
9 i: C' V! P# A; N* T4 X* T9 u1 }# mdup_str = strdup(string); 9 k! }1 P' {9 v- s8 \; o
printf("%s\n", dup_str);
7 `* Z5 E6 L% B4 P$ i+ Sfree(dup_str); ! Z# T N; W* [) g3 |/ S# ?* l7 @% q
return 0; 0 E# Q0 i# a3 H# ^! l& ?
}
* _: Y- Y9 R; D) }7 S/ H7 B- a, t$ [4 r* d, z
, a" y& p7 m" ]+ z$ |9 W; C
8 z6 ^* o+ d! m% c$ ?3 @
函数名: stricmp ; T1 x$ j/ j3 H. e1 S- r
功能: 以大小写不敏感方式比较两个串
# o+ j: S6 D: e& p. K用法: int stricmp(char *str1, char *str2); 4 r) Q2 a' O/ {2 q/ F3 s. P( `
程序例: 
$ z) L1 [( d- c5 o& B z- y#include <STRING.H>2 B: g0 H* J) e3 Z# p' q# e1 s' Y) o
#include <STDIO.H>
" `) h4 M i; B7 Q4 Wint main(void) : P- I5 Z$ l# J- z! W5 W
{ * |) ^3 K! j7 C n' Y6 G
char *buf1 = "BBB", *buf2 = "bbb"; - v/ q4 p# U) z3 q, l0 t; M2 P5 F
int ptr; , @$ Y0 {1 |4 k& S
ptr = stricmp(buf2, buf1); * D$ b' P& X* k( J% s6 l% \; r8 |
if (ptr > 0)
0 d/ Q( l! ?! M2 e" K) _2 b. Qprintf("buffer 2 is greater than buffer 1\n"); ' N/ b4 _% g* ?2 B, V2 F1 ^1 d
if (ptr < 0)
, a" i# ^& H6 p, pprintf("buffer 2 is less than buffer 1\n"); 
1 K2 I2 q& w! G7 R) |( Wif (ptr == 0)
! p- Z# D4 @, `/ ~9 A1 ^# Oprintf("buffer 2 equals buffer 1\n"); 7 p/ Z0 K5 K2 u5 e1 X
return 0;
! D: o/ q" T) p6 C- b} , t" y1 _( ~/ X! I* W
9 U1 _- v5 j3 }- V1 p0 a* s

2 ^; I' j6 \# z2 |, d6 X函数名: strerror 
2 m, o) j2 l( t! u+ @功能: 返回指向错误信息字符串的指针
6 ]0 z% f- B6 r' v& r) j1 l用法: char *strerror(int errnum);
1 ]( i% I% `$ ^6 ]程序例: & g- r+ k9 K% R! R6 \
#include <STDIO.H>$ ~3 Z6 {- _+ r0 k# X
#include <ERRNO.H>
- U k# Z M" }; ^: m% }int main(void)
3 X N1 Q) @+ F6 {# L{ $ g E/ W3 Y2 s
char *buffer; / a; V& C/ f5 I4 Z# v& I0 J+ _
buffer = strerror(errno);
& ?+ R) p/ a$ i3 {printf("Error: %s\n", buffer);
 Z% P6 _# H' q5 ]return 0; / m$ e- t% K" r! u; H2 y
} 6 r% B7 s( W/ [( ?( P5 |; f

& t F& T5 V& F5 f' o4 f! C/ ]& `$ W& u9 j
! j/ u- N8 G1 B, |
函数名: strcmpi ! N1 o! C7 M9 V# n
功能: 将一个串与另一个比较, 不管大小写
) I: c, K. R8 }4 _用法: int strcmpi(char *str1, char *str2); / [: w; V a6 B! S" z2 y
程序例: & s- |5 f0 x4 z# J5 u- M: R
#include <STRING.H>
( P% ^8 j1 O, c#include <STDIO.H>
) \' d+ S/ P) A/ R) ]int main(void)
/ ], C% X: d( @, s2 G{ ! r8 G+ _' e' Y6 C% U! {
char *buf1 = "BBB", *buf2 = "bbb"; + Z4 {" l( o) O0 `" t
int ptr; 
* J- v' y, K% P, g) ^ptr = strcmpi(buf2, buf1); 
* g3 s: e" ]8 e% Lif (ptr > 0) ) }. _, [- |/ K5 Y, a" [* l8 W( v
printf("buffer 2 is greater than buffer 1\n"); 6 M# l: @& s/ ~ x. G: o
if (ptr < 0) - v9 K% r* m1 @' j1 V6 N0 q
printf("buffer 2 is less than buffer 1\n"); 3 D0 @9 z& o. Z: G* r) ?4 U; d
if (ptr == 0) 9 I2 P% p' ~# D) C
printf("buffer 2 equals buffer 1\n"); % G( ^& i8 J; ]* z. t
return 0;
) [7 b8 m8 q( ~: H0 _} ! I! j0 E# {% O% ^7 o& r; U

8 ^$ t- V! n) i; i9 G2 K
8 V2 A$ Z3 E9 ?$ i& b
& R' E0 G' C" R! x1 O函数名: strncmp $ t/ S0 ~* @2 }! m' D* `* Q& x
功能: 串比较
! W1 y9 x0 h3 f- v3 t9 Y7 z用法: int strncmp(char *str1, char *str2, int maxlen); ^8 i2 _1 e# j( |3 n& n
程序例: $ `% ]' G: |( x0 j5 x0 D
#include <STRING.H>
( J- I/ X* y2 X0 l( `! `#include <STDIO.H># C0 k/ @1 D# L' V0 ?1 |; E
int main(void) 
! y/ m+ j0 J/ [: R' _& t) [{ 7 U# l6 N [* f/ W F: ]; d
char *buf1 = "aaabbb", *buf2 = "bbbccc", *buf3 = "ccc"; $ L; _7 ~1 z7 i l' A$ ^
int ptr; 
) q( ?4 L; m' ~: A6 k& L9 Q5 D$ p; }ptr = strncmp(buf2,buf1,3);
6 G5 `" P; ?# u2 G/ uif (ptr > 0)
8 o3 z, c8 i& ^printf("buffer 2 is greater than buffer 1\n"); : k! x. x4 K7 q- U- ` _7 v
else
8 ?- p; d( B8 [2 F+ Hprintf("buffer 2 is less than buffer 1\n"); 
" K, e" D- u7 w8 P0 q9 Rptr = strncmp(buf2,buf3,3); : A3 i, R# P+ ^9 f- h. {
if (ptr > 0)
1 }9 C: t! F, l0 H* gprintf("buffer 2 is greater than buffer 3\n"); $ c0 h' G6 n; _* O6 Z; `
else
5 [# g8 ]! b" @. S' y* U$ e) Gprintf("buffer 2 is less than buffer 3\n"); 7 o+ b% \# t0 e9 M) u N
return(0); 6 j" G$ h% l/ g; X5 M- ?' h
} 7 q( C7 M- c$ p2 b8 m+ z) t
3 P/ A' B& K& [, _7 m& a: {% ]
( v. R Q# c3 I! a
函数名: strncmpi s9 J- ]8 j1 F& ]! A$ v/ c S+ G
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 ) l# y8 }+ `( X0 L
用法: int strncmpi(char *str1, char *str2); 2 ?1 @$ C- N: [' ~/ b" D% `
程序例: ( t! E z7 O& l5 x
#include <STRING.H>
! ~1 J' g, w& }: @; }) \ \) h#include <STDIO.H>4 D4 A. e3 M+ Q* u! |
int main(void) X. K0 y% C9 Z# L9 h
{ 6 _- a5 J+ @" X* m
char *buf1 = "BBBccc", *buf2 = "bbbccc";
0 I+ |2 w- E" Iint ptr; 
$ {; _3 R# n. @$ \! l% ]ptr = strncmpi(buf2,buf1,3); 
3 c: l. i \6 H! rif (ptr > 0)
& `9 m/ A2 }* A, c$ J1 S5 Qprintf("buffer 2 is greater than buffer 1\n"); 
4 Q, Y* k9 x! G) C0 dif (ptr < 0) ~- H6 N+ J- _5 F% o
printf("buffer 2 is less than buffer 1\n"); 
 u- S+ Q: v9 X* bif (ptr == 0)
 q5 r; a- U9 e4 c$ e2 Wprintf("buffer 2 equals buffer 1\n"); 
$ c: t' f6 C" h; [* X0 |+ ^return 0; 
( u" ] O$ r0 n$ m! Z+ C5 e} ; h4 q u; {& r) J/ F

* r1 Z& q. W' i6 e1 X5 Z1 H* `, A- h5 y
函数名: strncpy ) k2 ]: s( j! `5 a" q4 e
功能: 串拷贝
! T+ X5 x" a9 m" L1 q0 v用法: char *strncpy(char *destin, char *source, int maxlen);
7 s" w2 E+ W# ?- p程序例: 3 q3 d& [3 {: L' F' q. S
#include <STDIO.H>
* d: d- f) Y+ F#include <STRING.H>
# o3 h1 [, y# `9 a6 Jint main(void)
) H Q0 H7 E$ E& |. K' V{
+ [& X8 F8 [8 s. D0 ^. rchar string[10]; . H/ C) R% X H/ A* I
char *str1 = "abcdefghi"; ; M* ~- o+ f. k# q; t. e w% Y3 _) w
strncpy(string, str1, 3);
; h7 L$ Y3 x9 x/ fstring[3] = '\0'; 0 _- h& s0 h# T/ n1 @
printf("%s\n", string);
0 g9 E, \ G4 d: X% K, hreturn 0;
) m& ~# t; X. G; s- X}
6 D: P* U1 K/ p' T0 x, a
* V0 S/ F U9 g
5 m6 U, ]. J4 \函数名: strnicmp 1 e' }# r" y" Z
功能: 不注重大小写地比较两个串
$ y- v. M3 ^1 n1 i) y! j用法: int strnicmp(char *str1, char *str2, unsigned maxlen);
. k7 }- `& R5 n+ k' [5 o% I& B3 k程序例: 
) c( A; }/ G/ r2 p7 x2 l3 P1 G, z#include <STRING.H>
" r6 B8 B. B, q, ]3 p" x1 }9 J#include <STDIO.H>- v/ j$ b% j5 ~1 _0 Z$ G6 U- T
int main(void) 6 G& s$ p/ R: o
{
1 f% F" }; O' achar *buf1 = "BBBccc", *buf2 = "bbbccc";
! @' l) g& o) Pint ptr; 0 W+ w6 Y- k( d' ]9 i: v& ?
ptr = strnicmp(buf2, buf1, 3); : W9 D! l: k c/ d
if (ptr > 0)
+ e7 r, U3 m) `0 w* `9 j$ P+ Dprintf("buffer 2 is greater than buffer 1\n"); 
, x Z/ e. e6 m: U1 K- zif (ptr < 0)
1 P, ]" l# ]9 S& a$ @* Hprintf("buffer 2 is less than buffer 1\n"); - m: ]: W9 t; \+ R. Y7 @. a) b
if (ptr == 0) 3 R# W) j3 V. S& ?2 N1 Y
printf("buffer 2 equals buffer 1\n"); 6 v6 v0 j* F& ~7 G6 E. w
return 0; ! t4 A3 l: R3 R+ d6 ]2 a. v. {# L
} 9 {; G$ c% o5 [$ e, l. F' [ r, O3 p
! t7 t* s+ K) e0 |& b4 `! \7 x

3 S/ r) ?- \' Q% u2 f/ `8 A0 n& d6 D5 B9 P6 [; b
函数名: strnset 
6 c9 c$ I* Q2 I7 B1 J* [- w功能: 将一个串中的所有字符都设为指定字符 0 {4 q% R) N, J/ A: x0 ?
用法: char *strnset(char *str, char ch, unsigned n);
0 O9 K, t# g. g$ n程序例: 
 g6 [' n8 B, N#include <STDIO.H>5 c7 C4 ?# ? A& [
#include <STRING.H>
+ }( k( d( ^: aint main(void) . M, X, _& H, m# e& o
{
" C& @) D1 G! l$ K) Z$ ochar *string = "abcdefghijklmnopqrstuvwxyz";
: y* _& t) C0 H) Fchar letter = 'x'; ; Z& @* t! f" V* m9 B
printf("string before strnset: %s\n", string);
/ `" x/ z) D, p: F- ? \strnset(string, letter, 13); + {& H( f2 H# [8 T- ^$ ?: l
printf("string after strnset: %s\n", string); 
* D% h, v( @9 b# n+ hreturn 0;
1 O$ A0 D; s" O! @) ^5 L2 b. |}
+ u& X' x- j! t9 K% ~# t' t/ [. R z4 D6 b* f
) C( J! X& X/ W% Y1 u1 i5 l
函数名: strpbrk ! x Z. E# ?. f Q) X
功能: 在串中查找给定字符集中的字符 ( _9 }1 \# M4 C2 f
用法: char *strpbrk(char *str1, char *str2);
2 \+ B' S0 J( u3 e1 C! f程序例: 
0 A1 I5 {1 g9 ?9 L#include <STDIO.H>8 C$ T v8 f4 p# `# T- k2 a2 u
#include <STRING.H>
& ~7 `1 D" M) _ U- ^ I$ Wint main(void)
; y) K( P3 Y% H{ ( a9 b5 h6 z# z( a4 R1 v
char *string1 = "abcdefghijklmnopqrstuvwxyz";
7 D$ Z* k9 _- W' Echar *string2 = "onm"; 8 R9 j. y$ P: Z8 U8 Q8 c. v0 j$ q- ?
char *ptr; 1 G+ B2 J1 z0 w. c- q
ptr = strpbrk(string1, string2); 0 M N9 b) @5 y) v
if (ptr)
/ J) y: }8 @& X" dprintf("strpbrk found first character: %c\n", *ptr);
' x' K' T Q* @$ Welse 8 v! [8 k& C* U$ |
printf("strpbrk didn't find character in set\n"); 
) [3 t6 N/ Z. W* yreturn 0;
1 N* l6 L% @% Q0 w$ B) n1 o/ n}
- o! T& m- X3 Q* x5 S& y' c c3 a% w
6 `, X/ Q# ~9 M/ |5 c

& _2 e6 q5 z5 p7 E% j* T- Z( {6 _9 @函数名: strrchr 4 L+ b. q: f; H2 _1 \
功能: 在串中查找指定字符的最后一个出现 + k9 z, w# P! v/ H9 B V4 V& k
用法: char *strrchr(char *str, char c);
6 I) U/ c# Y- [( _3 A程序例: $ J: Y% h+ A8 g/ B% [
#include <STRING.H>
 ?. ~' K. W* T. f#include <STDIO.H>
; S" a/ P4 U; M0 Z4 V7 X: A* kint main(void) 8 }& s9 N4 S) q: q' u# K
{ 8 ^" s1 w& R2 m5 u7 R. X( g- Y
char string[15]; 2 E$ ^6 G: d, u+ A9 @
char *ptr, c = 'r'; 
$ {& {, y' c, ~# K# b1 s* g9 \+ m# ~strcpy(string, "This is a string");
- ]) B% N+ {3 o$ e! R; F' Fptr = strrchr(string, c); 7 W6 x2 V1 Y6 N4 Z# b2 F/ d
if (ptr) 7 A8 q' Y& m: ?5 {( b+ G$ u5 ~
printf("The character %c is at position: %d\n", c, ptr-string);
9 U& {& l) k: \( R$ t6 V8 delse
/ E E7 ^5 H2 xprintf("The character was not found\n");
+ n! n9 J1 J8 V0 E7 @return 0;
1 B& S ~& F" C) I* ^- R% |9 \# Z} 
. U, }+ @4 S. F% C1 e2 J- Y9 f4 f. ]6 K% D c

5 @9 R. i3 J' G" ]2 H; H! r3 l, N6 v. S! I4 Y* P; C6 Z
函数名: strrev 8 q# X" f. H8 x* `. r6 [
功能: 串倒转
% x1 z6 `5 w# k G7 ^, ^ B) ?用法: char *strrev(char *str);
: S6 _3 Q# @" A8 n2 b程序例: $ k! d7 C1 c4 K! I1 ]. [
#include <STRING.H>9 p4 F6 @; z2 }7 E# s9 @+ b
#include <STDIO.H>
) t9 [: g0 }" q6 P4 V' j& ~5 }7 Jint main(void)
) K0 A: j) l- d4 A R+ n5 s9 W: \: H{ . d0 p" f# |. t( G, O
char *forward = "string"; 
* b# n- |. x. I7 I- R# \% cprintf("Before strrev(): %s\n", forward);
+ k2 \ F& |9 {/ ?) h p: Wstrrev(forward); $ Q/ [; a. W5 W. i& \8 D
printf("After strrev(): %s\n", forward); + K& C% M5 {: T8 X
return 0;
7 `" v" f( r7 i+ ]1 B1 d, a# Z} ' I6 G H* B# z# C, Z5 @3 w
( J# G% q* [2 ~' o2 q: e ]
函数名: strset 
. u. n; u8 u; j! s: E- Z4 \) Y功能: 将一个串中的所有字符都设为指定字符 9 k1 Y4 X- k$ O/ r! O
用法: char *strset(char *str, char c);
程序例: 
$ X; U# U+ d; F5 P& w4 j0 j#include <STDIO.H>) @, B0 P# E; f4 W0 U' A
#include <STRING.H>
- M7 q' S$ D- w% E& v* z% q- n( D+ sint main(void)
- b0 O+ B+ y$ h, w: N3 M9 F' I{ ( G5 c- V0 p3 i u9 E7 s
char string[10] = "123456789";
7 |: V/ s- r7 a" U& \' u8 Wchar symbol = 'c'; 
3 x# c6 x" T5 R% nprintf("Before strset(): %s\n", string); c7 G0 C2 u) T3 i
strset(string, symbol); ! j+ D8 G, Q. L/ d& f: `' B
printf("After strset(): %s\n", string);
1 d' C0 f8 I( V( m7 `return 0; ( {5 n6 k$ q X! V! [' v: u+ E
}
/ Y5 E7 f8 \2 x- [) N, [1 B2 ]0 P) |
) `( c, E, ]; q: } G
0 ]& E" p' x1 s' ~- w$ m% [, S5 a0 w
$ k+ W# j# @5 S6 y0 Y函数名: strspn 
( o q+ ^, O+ \& }. a! M功能: 在串中查找指定字符集的子集的第一次出现
6 i: b1 ~2 S) o: |6 ?用法: int strspn(char *str1, char *str2);
2 H. o0 H0 Z) l$ n程序例: " W- Z( A+ V6 {3 |! C8 c: n( _) b
#include <STDIO.H>
+ E) h9 d$ N0 w" _& \2 b/ c1 H- c#include <STRING.H>
- E& m$ A8 r- D- w) K) m#include <ALLOC.H>
4 L1 k' V9 R: \) N+ mint main(void) & b& |* U K# C
{
3 `6 W! [. E$ a/ H0 xchar *string1 = "1234567890";
 w, x( B2 t( F" wchar *string2 = "123DC8"; ' u2 e+ j& `; G: H
int length; 
! r5 o! Q1 H! Z* w7 plength = strspn(string1, string2);
8 v3 I$ f, Q* O6 W6 L1 ~printf("Character where strings differ is at position %d\n", length);
! L9 o5 F: j# v7 [4 G# V" Lreturn 0;
9 `. q4 G' Z' O) }* U# X} + m# J9 ]+ G; ~+ [9 H: `
2 a" _9 e/ a6 x5 f6 j
9 O. x% A- C; _3 q
函数名: strstr 
2 a* W) ?. \5 I; r2 ~功能: 在串中查找指定字符串的第一次出现
+ D- H- ^8 ]; M& v用法: char *strstr(char *str1, char *str2);
0 j# x* E3 R7 a1 f程序例: 
2 e1 a4 s6 i# x# t2 L#include <STDIO.H>
2 w, O j' V8 y8 N#include <STRING.H>
* u! _0 X. T# X4 @ ?$ ?2 Mint main(void) " h+ E& V' Y! X2 X) x
{
2 ~2 V q) K! Z+ fchar *str1 = "Borland International", *str2 = "nation", *ptr; " h- ` c5 R( K0 j3 C2 K
ptr = strstr(str1, str2);
1 H7 ^( p# \ N* ~% L/ p+ Qprintf("The substring is: %s\n", ptr); 9 R) e, C/ k% Q0 C8 Q1 c8 R, q& g
return 0;
. S1 B6 c: t0 T3 s) K1 M} / n# `# Z u7 b- }, m9 U2 E/ W- J

9 e% h% M; k/ [6 N
3 h3 A( s" Q, E7 T) A% P( U. O7 q函数名: strtod 
4 Q7 m. Q$ E+ P/ w功能: 将字符串转换为double型值
+ S; o% e& s6 y2 N2 B* \: E用法: double strtod(char *str, char **endptr);
3 S' B+ N" e4 |% O- d& c2 D程序例: # s* Y' J2 @* g1 y, H, z! ] [
#include <STDIO.H>) `! f. d/ j( S. [2 ~
#include <STDLIB.H>5 {) O0 }; a8 r
int main(void)
4 K/ i6 y1 x! G, \9 q- g{ 1 Y/ S2 y( I$ \, g" |( g# Z
char input[80], *endptr; % K' b+ K- H( P( a+ ]5 d
double value; ( b2 L4 C$ E4 ?% x" y( x5 i8 u
printf("Enter a floating point number:");
' O2 G- ]" L2 L- n- T' Pgets(input); 3 q! Z" t# f- _5 o+ L& J
value = strtod(input, &endptr); , F1 |% Y5 Y* b5 K
printf("The string is %s the number is %lf\n", input, value); ) D: |8 S3 g- f9 T- @
return 0;
; [1 h/ J) }$ \( v: ~" b. g, w4 x}
! V% T8 ?) H9 M: w* T5 n9 _* Z: M& v2 y5 W0 n- [2 U
# D2 ^5 ^0 p8 H4 h6 ?% r1 g; u

 |6 D0 i0 h; n- j, P函数名: strtok 0 W& w1 D& l8 a- Q/ @3 Q
功能: 查找由在第二个串中指定的分界符分隔开的单词
& r5 E! w% [5 f: j0 J用法: char *strtok(char *str1, char *str2);
8 ~3 |: C# N6 r+ h$ W) c程序例: 
( v$ U# n+ R7 ^, }9 C- l#include <STRING.H>
/ j. S) k+ g( m; @0 z$ u#include <STDIO.H>
& Z% D( m5 A6 c4 hint main(void) # V; E; j) b% u- U
{
 T( g' U0 B% e! }0 D$ P' |+ d8 Echar input[16] = "abc,d";
. S* H8 y2 V- {char *p; . H# S$ o y4 k& O9 M9 d/ J/ X
/* strtok places a NULL terminator
' g1 ]/ a# \3 p2 ^5 X5 s$ I' Min front of the token, if found */ 5 y6 q8 D+ D9 x4 T' U
p = strtok(input, ","); " f: z* s% c: B' [$ `0 H2 E- M
if (p) printf("%s\n", p); 
! U# F" m; [( y' b: H0 Q( H/* A second call to strtok using a NULL
8 s) g5 A8 `8 Uas the first parameter returns a pointer r7 G: O: @3 {" A5 Q4 i( {
to the character following the token */ # X" H# n3 v8 y' l# ~; A
p = strtok(NULL, ","); ) Z: D# I c* Y+ r
if (p) printf("%s\n", p); . o& ~$ t5 s1 J# _
return 0; " o% q% O: S9 |: |
} / {+ e8 i' K" X { F0 S

 N* k0 N% s1 x7 F: e+ y4 T7 l" z- p: Z! G$ z9 Q
7 F1 |1 v Y! N* X8 G( k$ e) W
函数名: strtol 
 w8 }, H- {7 Q" }功能: 将串转换为长整数 O4 A* S5 m1 s+ Z. G z& i. ?
用法: long strtol(char *str, char **endptr, int base); ( _0 m1 n9 J5 L. v n0 v5 W
程序例: 
" e6 L* g6 [% O8 i7 v" Q5 C! s" b#include <STDLIB.H>9 y8 \6 m9 Q% n
#include <STDIO.H>
7 _6 r4 L3 C: J, X7 mint main(void) ' v) P+ c' K2 a: j( m: W! j# s7 u
{
' D' _: f, _4 T# k/ n" m; [" Mchar *string = "87654321", *endptr; 3 L* e" a3 n8 M! E% Z2 ?
long lnumber; ; z- r! _ x! u' U& q
/* strtol converts string to long integer */ / R% w+ u) p( k' S7 o# G8 w0 ^
lnumber = strtol(string, &endptr, 10);
 W2 p1 H# l$ p- a$ Eprintf("string = %s long = %ld\n", string, lnumber); 
( q3 w# B0 H, m) v& p4 r7 breturn 0; y6 I5 N( u5 |* f3 R2 \" K
} 
% l" E; j4 e" h0 \" H1 f' j5 R
- V7 c! U' j( e3 L* ?& v函数名: strupr 2 b7 t5 _; F- Z4 R2 ?" S& |4 S
功能: 将串中的小写字母转换为大写字母
4 H4 P% Z# ~; a# l% }3 |( O7 J2 }& A用法: char *strupr(char *str);
8 u: H. \3 \! U3 t& k4 s4 k3 u程序例: 
9 E" i8 _% Y/ _1 C( v#include <STDIO.H>
. s. I# W- P" H+ ?#include <STRING.H>; x: D* Q; D- R6 s) G+ R3 h
int main(void)
; B) c- R2 i: S5 o{
1 T1 H# G& v5 f( G& x7 Q% schar *string = "abcdefghijklmnopqrstuvwxyz", *ptr; 
" a. @5 I' s! a2 \! u6 K/* converts string to upper case characters */ # b/ ^* g* i8 I1 y: @
ptr = strupr(string); 1 R9 i8 g M* _6 ?$ Z; @/ J3 A# B
printf("%s\n", ptr);
6 p- k6 p* Y ?: s$ W* greturn 0;
: k8 W) p' V/ |5 A, J- `* v} + u5 F0 x+ m4 q2 f0 @8 U/ M$ K- Z
" W, t3 Y7 [: u5 x
" a0 t# y* M' d' E$ I

: ?! e" A, p/ M. v函数名: swab / c, a! K7 v" Y# s$ D
功能: 交换字节 * j. y+ [: a' }; |- ?* b, r% g
用法: void swab (char *from, char *to, int nbytes);
4 K/ ~% ~1 _1 g" \) H程序例: " n9 n6 I2 Q) A. c6 \
#include <STDLIB.H>% {# q- I' Q5 [
#include <STDIO.H>
9 @8 Y; r: y7 A, R#include <STRING.H>
) P* @& Y3 }5 X$ w4 y6 V9 Gchar source[15] = "rFna koBlrna d";
1 I8 y3 D- M: e$ x. m# K# Fchar target[15]; 
- z! q5 a% P8 Kint main(void)
 ~+ |+ E0 G, ~" N& c& n) J: C{
7 s8 u v e- L E' _' Yswab(source, target, strlen(source)); 2 E" R( _7 {+ H
printf("This is target: %s\n", target); * Y1 }. G3 c. g) ?
return 0; % c% @0 y: O& P) p( Q+ Q8 ~; N
} ) c4 Y' t( E1 X0 b& f [
 l! m+ G' g6 C" F- }
7 F9 c5 T/ Y# P' y( G8 R) F3 |

: a! i) F4 H: ~. f函数名: system 
7 d, O: X3 G3 B3 d z7 a功能: 发出一个DOS命令
8 R% F5 Z' n% d用法: int system(char *command);
5 x8 `! c O+ @" a5 Q程序例: % p7 }) [9 w7 s @9 F! ?1 g; e
#include <STDLIB.H>
0 \' m E! S6 b1 g4 B. O#include <STDIO.H>
! t/ e( ^/ |9 ^, C$ l8 y7 v- V6 c# Hint main(void) ! a, q% J% y& s6 \5 K1 @! x0 N
{
( l& B& J: j+ A D+ A% Eprintf("About to spawn command.com and run a DOS command\n"); ; f. S8 f' S3 {/ g
system("dir");
% g z4 ?4 p1 y: \! ?return 0;
# ~: a/ G: z. t; _} 

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