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); 
2 n3 d0 |$ d' J8 g( Q/* display the gray scale */ 4 m: V# F. Z ~/ v. D2 l
ht = getmaxy() / 16; + r$ f4 A8 c7 j
xmax = getmaxx();
& x' _( D" F) E" c3 A$ l6 Zy = 0;
: J+ M0 A7 Y+ @for (i=0; i<PAL.SIZE; {
4 ]0 v3 h( G2 ysetfillstyle(SOLID_FILL, i); - n3 ?8 X- Q9 O1 c% `2 p
bar(0, y, xmax, y+ht);
( q7 ^) i' I9 G2 i0 }y += ht;
7 C7 t( }- r5 u1 a/ W} . ?$ z7 F1 y* \9 t
/* clean up */ 8 w$ b" R6 I; I5 f& J) A
getch();
7 ^) L! T; k; n5 a5 C* S" }closegraph();
- B5 _7 ?8 a# preturn 0;
- e$ t) M& d9 K6 J} 8 P1 k6 l2 G0 t7 t! v1 l- V
! F; F' [2 w/ M& q+ ]/ |
3 I8 r! V n4 w" d/ ^$ C6 q0 m
2 }$ F$ X+ I. w, t
函数名: settextjustify 2 L* _/ a7 s# j# R8 H& c
功能: 为图形函数设置文本的对齐方式 , M& t- a. X% R; K7 W; e' s
用法: void far settextjustify(int horiz, int vert);
7 {1 v! r4 _: {/ ^2 G) X$ ^* o程序例: " r* i, D3 C; L" f$ G+ D
#include <GRAPHICS.H>
6 c1 x( a0 K: C5 N2 R1 ~#include <STDLIB.H> _8 F. c8 e! e8 E0 Q0 u
#include <STDIO.H>
% ]5 B% T) o- T. O! p#include <CONIO.H>$ k% x) ]2 h4 ]( @. d& s
/* function prototype */
, G2 G: B( Z; M: r9 r8 M5 h+ b0 l$ wvoid xat(int x, int y); 
, p4 O; e" m! V1 y- p/ h7 T# R/* horizontal text justification settings */ c" T0 V7 y4 I, |
char *hjust[] = { "LEFT_TEXT",
, o8 B( ~; S/ Z' Z* X0 ?"CENTER_TEXT", 2 |4 W3 `6 @# x; F) ~5 g
"RIGHT_TEXT" & i9 ]2 \: m( e3 L0 t9 ~; J$ a
}; & P& p4 o4 h- t: e! k% R
/* vertical text justification settings */ N6 P% j5 [; H$ b8 [' q& l& [
char *vjust[] = { "LEFT_TEXT",
4 v) E2 w7 E! d; Y/ _2 Q"CENTER_TEXT",
8 r7 A- S, n3 p" ^9 Q1 C' U# m"RIGHT_TEXT" : {" x( E u+ g( I( u1 n
}; 
4 J! v) G" b- B( Y8 O4 ~" Yint main(void) . [) y0 ^8 S; x1 v- K; a% m; R
{ 0 C3 d; g! y6 D+ k5 c
/* request auto detection */ + V3 J" o; N7 {- G
int gdriver = DETECT, gmode, errorcode;
" y( R/ `% ]! ]6 S+ e& e# H( Qint midx, midy, hj, vj;
" A0 y' x% N; E; h vchar msg[80]; 
: V" X8 t# s% [& G/* initialize graphics and local variables */ 0 _6 k2 t. e2 f" s8 _1 w
initgraph(&gdriver, &gmode, ""); 8 m: C& x# e7 \4 V- Y3 t$ _7 \
/* read result of initialization */ 6 T& {. e5 B/ x# u
errorcode = graphresult(); " q$ X5 t f3 e( h5 }; h& X
if (errorcode != grOk) /* an error occurred */
/ S, e2 b" ?- n# z, c! e{
# T l% `% h$ \* @printf("Graphics error: %s\n", grapherrormsg(errorcode));
) ^+ z( u3 D% L# {2 Jprintf("Press any key to halt:"); 6 q( j. B0 j( [
getch(); 4 l3 b% B* ]/ d& `# j. S
exit(1); /* terminate with an error code */
8 s9 v5 C; z. B5 |! t2 O' y) v" F& t; X} 
8 M9 d; y: u* v9 X3 O2 g. H! xmidx = getmaxx() / 2;
, @( ~" ^6 v2 L# T4 u' T$ Fmidy = getmaxy() / 2; 
5 Y' ~, k/ k d& G1 I* {9 ~/* loop through text justifications */
0 }: A; I; k1 W, f. Ofor (hj=LEFT_TEXT; hj<=RIGHT_TEXT; hj++) 8 W$ v( @% Q: ]% @
for (vj=LEFT_TEXT; vj<=RIGHT_TEXT; vj++) ( h9 G% o8 u2 ?* a% I: ~
{ ! _9 F$ l3 f3 J) v. Y
cleardevice();
: V# Q0 I% Q. @4 S6 Z E7 R/* set the text justification */ & b; K6 Z( o) y! F
settextjustify(hj, vj); 
0 d7 P4 |1 n1 M* D/* create a message string */
/ F' j* k i4 I+ V O% \7 Esprintf(msg, "%s %s", hjust[hj], vjust[vj]); 
0 Y0 K# h0 M K8 {; u0 Y- E/* create cross hairs on the screen */
. H: A" f; Y0 L0 Lxat(midx, midy); 
! }- i0 y4 a! l1 r- M" C* x2 S: b4 f/* output the message */
0 \9 e4 @& C: W2 a' F# @3 J, _, ?, Kouttextxy(midx, midy, msg); * Q1 d! ^/ D: G( |$ a E+ F# D
getch();
( s" j, n1 [2 u" u} 
# r% h }# Y! b0 ^ ^/* clean up */
% u$ k; c5 i/ c% W$ U+ qclosegraph(); ) h$ I$ w" C0 U" g. F( `$ ]( {
return 0; ( u# }1 d& X& @* ?
} ' W% n8 h' Y5 Z
/* draw an "x" at (x, y) */ 7 M2 [( f+ t" |! B9 o0 g6 k
void xat(int x, int y) a/ W' `) K4 d# d4 j. H4 F
{ F1 D7 B2 }1 {/ b7 M
line(x-4, y, x+4, y); , F+ `/ S* N$ |/ k6 ]
line(x, y-4, x, y+4); - \# b. g `- n
} 
) ^ j8 }* d6 J9 o
5 u8 M4 l& f7 Q4 S& _ B; o: l' Z7 U N2 t
函数名: settextstyle 
# ]$ N& w9 j) k' z- y* E, ]. Y功能: 为图形输出设置当前的文本属性 * [- q4 a8 w& z2 D+ \! ]
用法: void far settextstyle (int font, int direction, char size); 9 e, z, T# A! s7 g7 I
程序例: ) g' R+ T8 H; ^5 [4 n' \3 Z5 s
#include <GRAPHICS.H>
! p6 V- b$ b# d8 ?5 `#include <STDLIB.H>
8 x h" }6 K* e7 Y#include <STDIO.H># d- u" F, V0 c) G9 Y0 F3 J( i
#include <CONIO.H>$ N# O* [2 |% u0 ]" J$ E, b2 P3 J
/* the names of the text styles supported */ - g) b6 T) M* j/ o% j G+ b
char *fname[] = { "DEFAULT font", - }: Q" ^* J- `% M' |- U9 h
"TRIPLEX font", % _, F% g( b) A1 I
"SMALL font", 3 j* G8 A' T( U) v
"SANS SERIF font",
" @; r7 L' A8 n$ c"GOTHIC font" # X) V+ g/ g( A% n( J% F
}; 
' V% I! K9 H q; D3 B( zint main(void)
: O; s1 P4 H# e, p, e{ ( \/ ]" v* V, C+ p; m
/* request auto detection */
* Z3 b6 W5 u5 T4 x# C3 z% X6 N9 rint gdriver = DETECT, gmode, errorcode; * M" c q' X s, v* C- _
int style, midx, midy; # }! A6 e2 s2 M+ y4 [ L
int size = 1; 6 K# Q& ]2 t2 \+ x5 t
/* initialize graphics and local variables */ ) A% a. F: l0 ]0 }% O
initgraph(&gdriver, &gmode, ""); 
2 S. c& B! W8 i5 q. H% r& `/* read result of initialization */
6 ^5 ?9 y9 o# ]errorcode = graphresult(); F$ @. B+ E9 G( J6 B
if (errorcode != grOk) /* an error occurred */
3 t+ w% G7 H5 ~2 c{
5 Z+ Q4 X( v- ]0 t+ Jprintf("Graphics error: %s\n", grapherrormsg(errorcode)); 8 i& P ~/ ~+ ^: y
printf("Press any key to halt:"); $ F$ j+ }2 L3 S9 I9 [, X0 A
getch(); 0 I; s9 J1 o: {' r1 m: s+ `* n1 g
exit(1); /* terminate with an error code */ 1 i. P' n0 K$ L T
} 
, k2 P i3 d- G' Omidx = getmaxx() / 2;
: x7 S8 ^# q- X' O" `midy = getmaxy() / 2; ! D( R$ v3 @' @% ^
settextjustify(CENTER_TEXT, CENTER_TEXT); 
* R- \: a' k: ^ K5 e G# D2 d; L/* loop through the available text styles */ : X9 k; n( ]6 S4 t7 d
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++) * S- q) i% O0 @+ i+ M4 l
{
7 `5 c7 j9 y9 i3 Lcleardevice();
5 U0 w: q9 D, }5 h( D* @if (style == TRIPLEX_FONT) , A0 n: M7 C/ p! k* `! A3 P
size = 4; ( {' L l# [) ^$ J: E5 D
/* select the text style */ - U: n, @* S! r4 R* K: H8 ]
settextstyle(style, HORIZ_DIR, size); & W# K/ r) `4 S9 s ~) E. @
/* output a message */
- s G0 `* o. v6 Q7 t9 P4 i. N2 A& ?outtextxy(midx, midy, fname[style]);
! _; U; c/ M( w# Ygetch(); + s$ o% u$ @6 ~6 {5 D
} 
( `, z5 K9 }1 Q Y" l/ g/* clean up */
 e. M* l) N4 ~" L r* Kclosegraph();
- D0 u$ y3 U: g e" q) I# q/ \return 0;
: m9 v% ]; i+ B0 D' O} 5 W9 Z; ~# z' s/ ?

- I( [' `3 ?& A. Y3 k/ r! L
; P. U2 ~ j* Q; s I函数名: settextstyle 
; h* C5 D( D; O: N Q: [功能: 为图形输出设置当前的文本属性 ' g+ P4 T, n8 W" r
用法: void far settextstyle (int font, int direction, char size); 3 j* `5 I# o& a( H
程序例: 6 j# O9 L Q! W$ ?4 H$ B( s
#include <GRAPHICS.H>
; }. u. e% ?% ~6 S; t#include <STDLIB.H>0 Z' c# c, @! z' E6 _. l
#include <STDIO.H>0 x. D! x6 M$ B, v! e
#include <CONIO.H>" q& R. g [ ^8 t& C
/* the names of the text styles supported */
) i/ q, ~; t9 z+ B% f0 Jchar *fname[] = { "DEFAULT font", 0 H l9 G" ^" u1 a; ~$ a- w
"TRIPLEX font", : B0 f `! }+ e& Q5 e
"SMALL font", ( j8 e& z G* M' w }3 n
"SANS SERIF font", ( k6 y G {* ^$ k- j3 T
"GOTHIC font"
9 k# R5 v0 V4 D}; 
% Q X+ [, s) M: n" S, S( Y' Fint main(void) 6 T( e1 F, u% w" S- {# G
{ 8 _# x7 j8 ?" u7 X' O: y0 l
/* request auto detection */
) ~( c: t, i1 q2 l3 oint gdriver = DETECT, gmode, errorcode;
2 |* o2 F# c% h1 s: u/ yint style, midx, midy;
9 M# x3 w0 o4 y& D I' K+ e* E6 Aint size = 1; 
6 k% y$ w' Y4 o& }' Y" B6 |/* initialize graphics and local variables */
& s7 m% k! c! e: ]$ k/ [initgraph(&gdriver, &gmode, ""); 3 l5 Z: r2 A1 L
/* read result of initialization */ : ?: J2 b9 ^2 ?+ b
errorcode = graphresult(); & }' B! c4 m) o' b
if (errorcode != grOk) /* an error occurred */
/ j T1 X, n" F; x) y+ N{
" D9 f* j' f* r7 y0 h: jprintf("Graphics error: %s\n", grapherrormsg(errorcode)); / g9 H/ b' }* l
printf("Press any key to halt:");
" x0 L5 `! V, F8 sgetch(); 2 `8 m4 {- u2 @( g' s( J9 G: J
exit(1); /* terminate with an error code */ / q: f, P! K. D+ P1 d- D4 T
} 
* V0 \6 J. ], bmidx = getmaxx() / 2;
! s5 t0 q* H+ w% J4 qmidy = getmaxy() / 2; 9 L& I3 i# {4 {% l
settextjustify(CENTER_TEXT, CENTER_TEXT); 
% o7 i; B0 {& c' M+ f' C. n0 @: g/* loop through the available text styles */ 8 B. f7 p2 X: O* U3 \
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++)
& a+ N: V- Y# u{ ! R. y) o' g0 [, Y3 i( @2 a2 F, B
cleardevice();
5 a' Y; Q, o. D2 wif (style == TRIPLEX_FONT) 2 h% X7 n) i, n, ~1 o: r
size = 4; 
. B O0 e6 J9 D9 {- X0 c/* select the text style */ * U9 O1 c. b3 W0 S( K, ?2 A0 R
settextstyle(style, HORIZ_DIR, size); % s7 {# M6 x+ {% ]# p# N1 u
/* output a message */ ) I B: Q7 Y: a. p* h1 ]
outtextxy(midx, midy, fname[style]);
1 A# i$ U* j( f5 ?2 t7 wgetch(); ) Y+ L, |5 \- q# ?0 X
} 
! S! A4 s* z' S& ?/* clean up */
& v0 O H9 ? w( u! G U2 [closegraph();
- d3 k* E6 r. U2 I+ l/ yreturn 0;
* d' i. Q' [; F% B} 
8 w5 t) T5 Z( D- ]% K5 x* ^8 U1 {& R8 {; K* w; T
3 w3 s. X! _+ w2 \5 I
函数名: settime # F* m6 J% t! c' x
功能: 设置系统时间
: i* O5 K& n- W! N$ I8 V用法: void settime(struct time *timep); ! c+ k) l* R9 P) m- e3 @% P
程序例: . v* \1 u- N! f# r6 d
#include <STDIO.H>
5 }* p+ s' D' S7 ]- F t" x#include <DOS.H>7 G0 J2 k' G: b; q
int main(void)
3 _, [: z0 B6 c* ~" q{ ) Z# Z h5 N& C! }! ^
struct time t; + h- e+ X# s \* e
gettime(&t); 7 I! j5 C& k# \4 _0 W/ I) C- I
printf("The current minute is: %d\n", t.ti_min); , k. r0 X0 b- b% L) C4 a1 y
printf("The current hour is: %d\n", t.ti_hour);
/ Z$ X2 Z* I9 N9 I9 s: Nprintf("The current hundredth of a second is: %d\n", t.ti_hund); 9 t: S, H1 i9 [; z7 x
printf("The current second is: %d\n", t.ti_sec); 
! H. b4 c( L* U% O1 d. }/* Add one to the minutes struct element and then call settime */
3 s; `& A, F1 T' G0 j9 wt.ti_min++;
- h- `" V) x1 J C! z& c8 }settime(&t); 
7 H; `( y3 l$ h6 i! [# z- freturn 0; ' V; r) C, Q# E8 Y7 V# G) V
} 
4 Z. H' u* O6 {, t% R# D# n0 S, j

, y& x% w0 h" M! h6 B5 K9 M函数名: setusercharsize 2 c# Y# |6 M; ?, A3 s" e1 t: q
功能: 为矢量字体改变字符宽度和高度 * m! u, A# _! d( [) {$ M; [+ z
用法: void far setusercharsize(int multx, int dirx, int multy, int diry);
" f D2 i7 i+ z# `- f程序例: 
) u0 K% T" m" X5 k5 E- F#include <GRAPHICS.H>+ G1 d8 q( z2 e Q+ `/ s, V
#include <STDLIB.H>/ K5 a7 Q. P1 Y1 U8 [9 m& Q- g
#include <STDIO.H>& L) z- E+ W: \9 ?' x
#include <CONIO.H>9 ]9 J5 C. z0 N& v: U9 j
int main(void) + ]. g A) s0 @' d
{ - {" }( i# S, y4 _
/* request autodetection */ 3 W8 n- m. ^) p" U) r* Y
int gdriver = DETECT, gmode, errorcode; 
) X, H1 L" V* T$ R8 Z/* initialize graphics and local variables */ 3 F5 i$ y/ K/ W6 ?0 o
initgraph(&gdriver, &gmode, ""); 
: d1 @( ~ a n( y/* read result of initialization */ H% }' I2 Y# G
errorcode = graphresult(); , I4 l) B* B- j- n
if (errorcode != grOk) /* an error occurred */
9 s: V f/ ~: w( V. F{
3 [9 k3 i; T7 w5 s# gprintf("Graphics error: %s\n", grapherrormsg(errorcode)); ! Y2 k6 x& [& ^2 Q6 y2 B
printf("Press any key to halt:");
6 y- ? R8 ?; A3 B# i1 B* i' p: cgetch(); - j5 J6 R3 L" S+ R/ y, k
exit(1); /* terminate with an error code */ ( u, V# o" P- g7 G8 P! z% s
} 2 ~/ f' [2 j8 {" I
/* select a text style */ , `3 [3 i* ?2 A' \( I4 S; a
settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4); 0 i$ n) ]+ n8 N! z" B% N$ {
/* move to the text starting position */ ( e9 ^! v3 Q1 P5 D+ ]8 e
moveto(0, getmaxy() / 2); # o/ `. A3 A: _% @
/* output some normal text */ " a0 X c( i5 }0 ~; W9 }* l5 p) t
outtext("Norm "); 
' l: _% y% }) M0 H- |; P/* make the text 1/3 the normal width */ N0 R7 w$ ?, @+ `, p. ]
setusercharsize(1, 3, 1, 1);
+ A0 _( Q6 ]1 f! uouttext("Short "); 
6 v8 {% R% ]* g' @. Q2 v- q4 ~/* make the text 3 times normal width */ 2 @; I, G9 w) j! N
setusercharsize(3, 1, 1, 1);
" t# P6 @, b0 ^1 d, Q5 Iouttext("Wide"); & W6 s0 I( Z! x$ f8 p
/* clean up */
3 q9 q7 |1 K. _. D2 M" {getch(); & ~- ]1 P; X h- w$ g% f- I8 V
closegraph(); 1 e9 m0 }) F! R3 ^. e& S4 T+ P
return 0;
2 g8 [4 t* i$ f1 C( Q1 @2 i$ r} 
8 V/ j' r7 o( y! G0 a- r- H9 n: K+ b( O h. V
函数名: setvbuf & B9 o9 e* ~7 l1 N
功能: 把缓冲区与流相关
) T% Z. `! P/ k* l4 p用法: int setvbuf(FILE *stream, char *buf, int type, unsigned size); - I/ W" q9 D6 l2 f
程序例: 
- Z; v. \; ^1 t& O# W4 u" K( z#include <STDIO.H>
- @+ g: [1 Z' K) { b9 xint main(void) 4 U8 `* l' _0 M- Z5 F. R
{ 4 w( h, ]. y( y5 d
FILE *input, *output;
! q/ V5 W5 R' m I+ o1 vchar bufr[512]; 
% D( k+ J1 @- U" v: \5 Tinput = fopen("file.in", "r+b");
; C9 M, w1 t3 K3 b, [& }output = fopen("file.out", "w"); 1 ?. K, [( G5 d# i, U" _
/* set up input stream for minimal disk access, / x, R9 U3 ^; h4 o7 A
using our own character buffer */
6 i# Q1 Q) S+ a) {1 w5 S) D( iif (setvbuf(input, bufr, _IOFBF, 512) != 0) , ]' t. A: n$ \3 R" B7 k
printf("failed to set up buffer for input file\n"); * V+ g! p7 I6 `- h5 Y
else
6 \: q' ^( z4 t' H3 r4 @* jprintf("buffer set up for input file\n"); 
) ]4 Y3 M8 C- G# ~; V4 `+ `0 t" |/* set up output stream for line buffering using space that
0 `8 f& v4 ~& Q. s# ^1 f( ~, Xwill be obtained through an indirect call to malloc */ ' `: w% j8 f- u, `" R- A
if (setvbuf(output, NULL, _IOLBF, 132) != 0) & D" X; ` |9 V' v- p$ f! {0 r
printf("failed to set up buffer for output file\n"); 7 v0 ?" g) f+ h- t: c3 v
else
) T4 z# j b* I+ u4 |printf("buffer set up for output file\n"); * {* ]: Z; v4 h% S% x; `* Z6 w5 ?
/* perform file I/O here */ ( Q2 }) D; K5 I+ c6 J$ t
/* close files */
5 M( v! d+ k! Vfclose(input);
7 ^% S1 ?0 f" g0 D# G& r) Jfclose(output); ' O% B5 C: t; `% R
return 0;
; p5 T* H" v/ @8 u7 ~; Y} 8 n" N1 ^- |0 |) ]; [+ P
$ `& d. L! E0 q' _ s0 C
- c4 x: T: l- ?0 p& I4 L8 o0 s
; c8 s% K2 w5 J7 K$ O& K, @8 m
函数名: setvect 
/ Y; x; d) W! U) t, u/ F功能: 设置中断矢量入口 p, y$ \4 |; z
用法: void setvect(int intr_num, void interrupt(*isr)());
" r* b% B; p* j$ Z t程序例: 1 \6 ~; v/ {) T! p! Q
/***NOTE: 9 c9 {2 n, y T( F' z; k
This is an interrupt service routine. You can NOT compile this * }0 |4 ?2 ]& K
program with Test Stack Overflow turned on and get an executable
; b2 ~* o, Q2 A! q9 G+ ?) ~file which will operate correctly. */ 
+ r- T. G2 `1 @) T! `; \#include <STDIO.H>: e8 _' I) X4 M! e; b5 O0 X
#include <DOS.H>
: |! D+ i3 S$ h7 H- t$ @) A0 \/ s#include <CONIO.H>
+ I7 I6 p9 X: ]#define INTR 0X1C /* The clock tick interrupt */ 
9 h4 J! S* Y# n s; v# |void interrupt ( *oldhandler)(void); - F2 e6 ?4 s3 u; O" q5 r
int count=0; 
/ v2 H6 k3 @: |# B4 m3 n9 I2 Mvoid interrupt handler(void) + E. \% U; D+ ~+ z+ \$ n* p
{
8 d9 V2 s0 Y! K/* increase the global counter */ ) f7 U! g0 b) A @9 ~6 k1 O
count++; 4 i' Z J, s m- e* X
/* call the old routine */
4 r0 P0 _; H' I: N2 ]/ P3 soldhandler(); : Q) I: z, I0 B
} 
int main(void)
{ % r0 U% s+ E( M' o& a4 L* @- u
/* save the old interrupt vector */ ; m3 k! F, F# W/ `3 E" O
oldhandler = getvect(INTR); $ B3 X: Y. Y5 M+ y( k7 z& F
/* install the new interrupt handler */
; b0 E" `8 E, z D- V; Csetvect(INTR, handler); 
- x* {0 `& w/ t5 W. f( g }; Z3 Z/* loop until the counter exceeds 20 */ + v' r& `% k, `1 k7 H* k
while (count < 20)
. ]% p" A5 G5 @- B( t" R+ K4 [printf("count is %d\n",count); 5 z* [, b) [4 Z1 U
/* reset the old interrupt handler */ 2 v6 `* ?$ ]& m9 O4 Q( S
setvect(INTR, oldhandler); 
# }9 h" R! \. y: T0 \return 0;
5 Z5 S% T6 b5 n! Z2 A/ k- y}
' G/ V1 N8 E. }% T7 K8 @6 T ?
' F: d, y7 m. n. z- J, v; w- E8 T+ K# q
函数名: setverify 
# D1 q! i" z0 |3 }功能: 设置验证状态 - _ [ x. F7 f8 p( _ s
用法: void setverify(int value);
! f7 L/ H$ N$ m程序例: 1 t* ]1 z* T; N, F( z C# r; Y
#include <STDIO.H>
8 }+ u$ Q* ?/ D/ m( ^#include <CONIO.H>
2 w% @5 O! d( L, K/ D( o#include <DOS.H>
3 e9 S# _: W+ L% B: gint main(void)
2 _9 ~$ C. P) W4 ~. { `; _9 I& b{ 8 S/ k4 J3 z) L! q+ x; Z8 x
int verify_flag; 
 q; b2 u% Z0 V! Xprintf("Enter 0 to set verify flag off\n");
* ]: B! B1 `7 N/ ~8 F- n7 Zprintf("Enter 1 to set verify flag on\n"); 
6 Y2 F1 [5 h# V9 @: Sverify_flag = getch() - 0; 
3 a- [# U' _: [6 ?3 Vsetverify(verify_flag); 2 ~' Q: S q$ u% _4 @2 E9 N
if (getverify()) ( x; S, S6 K. Y" S
printf("DOS verify flag is on\n"); 7 i2 \0 k5 ?5 D0 c/ F
else
9 k) S% n; c( z& X8 _3 Aprintf("DOS verify flag is off\n"); 
9 Q1 U! b: G4 o |; d+ S0 ^return 0;
3 P+ ^6 C, X. K( J0 }, ]) p}
4 ~) i3 g; q% z) Z1 H4 e: N
& }% h! f8 q- @; z
* w5 c& j/ `! s6 k: Z( `; O函数名: setviewport ( P9 V0 m0 i- H* ] \* s
功能: 为图形输出设置当前视口 ' q7 {; e+ u# U+ N1 E/ k1 \
用法: void far setviewport(int left, int top, int right, - I9 U D9 Z% }4 M
int bottom, int clipflag); Y$ r# H# @) p
程序例: ) I# E) e6 i! y: Z
#include <GRAPHICS.H>7 S8 F: l8 N# ?5 @1 D/ ^# ]
#include <STDLIB.H>
. L. b) X! n) f8 I/ Z# s8 N#include <STDIO.H>8 a7 l9 Q/ l% T
#include <CONIO.H>* j" N: ?. c8 @, V$ x2 K H+ @8 \
#define CLIP_ON 1 /* activates clipping in viewport */ 8 R1 m$ c P0 \& U: S% ? F, T
int main(void)
+ I+ O0 D3 c0 j' t: l{
9 q+ [/ _3 O M/* request auto detection */
2 u3 s" m* X9 J; _. P1 Uint gdriver = DETECT, gmode, errorcode; 
+ Y8 _ x0 p" d1 Z; R3 J/* initialize graphics and local variables */ 8 ?& \/ C5 `1 g6 H
initgraph(&gdriver, &gmode, ""); 
1 ^( a J2 o7 I5 r T% N/* read result of initialization */
+ n5 ~3 J$ e. X. @ c0 Gerrorcode = graphresult(); 3 x* e( t3 N2 {; F
if (errorcode != grOk) /* an error occurred */ & k; Q u5 r0 @5 a& _) t8 \: i: H
{
! u) M! ^0 ~! Y( Pprintf("Graphics error: %s\n", grapherrormsg(errorcode));
0 d$ ? h3 q0 W* W& hprintf("Press any key to halt:"); - e/ i" ?0 P" T6 G& t
getch(); * ]5 p" A$ }0 l% ~/ T! \0 l
exit(1); /* terminate with an error code */
- r! f0 F J9 |} - `4 h2 E. Z' X9 c4 P- o
setcolor(getmaxcolor()); + V7 S7 Z) R4 a
/* message in default full-screen viewport */
/ R* e. Z3 ^+ P H5 couttextxy(0, 0, "* <-- (0, 0) in default viewport"); + t9 g' O* N+ H8 b: ]: e
/* create a smaller viewport */
1 N, f9 \* a8 {+ b8 Xsetviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON); 
0 [3 v; |6 \/ w2 j/* display some text */
7 x: ?; i* v* Z0 ^. E: [5 @outtextxy(0, 0, "* <-- (0, 0) in smaller viewport"); 
4 l3 n6 X5 W2 j3 |' T" p/* clean up */
$ Z& S# B( S5 x3 S! Z2 ngetch();
1 E& I \+ S- k! I3 M0 Iclosegraph();
0 L* m J6 {9 p2 kreturn 0;
$ [9 Q S G$ w( C} " t2 v0 H/ R# G# K$ _5 D# w

+ d7 ~' W H5 F: h# ~/ [/ E2 P4 l9 p, x {5 a0 R& D
函数名: setvisualpage ( I& d2 o! j* H1 d1 m' p
功能: 设置可见图形页号
- Z1 ^$ m. ?8 a) x$ ?用法: void far setvisualpage(int pagenum); $ I/ r7 d* |. ?7 ?
程序例: 
; m$ N2 \6 I& K9 {- U( |7 n#include <GRAPHICS.H>% B2 ~3 P a/ c4 F1 `9 ~+ g9 _7 }
#include <STDLIB.H>
1 G( | J8 [2 s+ G#include <STDIO.H>3 g, d: Y3 [6 K' V( j k) S, @9 v
#include <CONIO.H>
; s6 k+ m r; h" @8 t8 g2 ]5 M5 Uint main(void) 9 w5 P4 {# g; }
{
; n/ v6 ~1 i/ |/* select a driver and mode that supports */ R* I- \' |+ G& K! z* v
/* multiple pages. */ ! A/ u: S! Z$ U! q% | ~( w6 k
int gdriver = EGA, gmode = EGAHI, errorcode; |$ c' `+ z$ ], _
int x, y, ht; 
8 k& t5 O4 s, u, Y* F) U% `/* initialize graphics and local variables */
5 M, h% p; k6 t; O2 c: dinitgraph(&gdriver, &gmode, ""); 
: d: I! G+ |# t, G) J/* read result of initialization */ 7 n# l+ d; `$ G& K0 r, o2 `
errorcode = graphresult(); 9 S. z4 S1 T4 h6 Q" \
if (errorcode != grOk) /* an error occurred */
8 F2 y8 L& {3 A: d0 E& j1 G! f{ 2 f" h' M' B; q( @1 @
printf("Graphics error: %s\n", grapherrormsg(errorcode)); ! H/ I( \8 y* Q
printf("Press any key to halt:");
. S6 z2 b! d1 N! kgetch(); 8 S, J$ g0 t9 o: V X
exit(1); /* terminate with an error code */
 `- V8 T7 g; f" j1 ]: j# A} + q0 W2 k4 Q, w$ o: S4 f
x = getmaxx() / 2; $ ~' V9 W/ S( K1 z! A
y = getmaxy() / 2;
$ L2 A9 ^7 p2 lht = textheight("W"); 
; K% T+ ]" }) g+ t0 O/* select the off screen page for drawing */
" y) k1 J5 _9 k: B" {+ W( J/ Ssetactivepage(1); 
' z) [5 I: {) n. Z4 u0 d7 S9 T: ~ n/* draw a line on page #1 */
6 B& c: j7 ~/ ?line(0, 0, getmaxx(), getmaxy()); 
7 e ~3 @4 Z! }. u; [/* output a message on page #1 */ : h# ~$ h' Z9 ~# J+ C5 ~7 _4 |5 L0 \$ @
settextjustify(CENTER_TEXT, CENTER_TEXT);
9 m M$ g- f# Z5 Z! N; b* x) Routtextxy(x, y, "This is page #1:");
0 T1 O- ]; F, C6 g) ]outtextxy(x, y+ht, "Press any key to halt:"); 
' S/ [, S- S6 V- L. R/* select drawing to page #0 */ / R1 C9 G! L" V$ a# v& n, F
setactivepage(0); + W8 l% R! I; s! r
/* output a message on page #0 */
; N" }( p; Y' e3 Touttextxy(x, y, "This is page #0."); 8 }/ A8 m& v0 V6 ~ x
outtextxy(x, y+ht, "Press any key to view page #1:"); ! Z0 ^' p5 K8 X
getch(); 9 P& I3 d* i( b6 |) j
/* select page #1 as the visible page */ 0 y4 t% V* O0 U' B, U
setvisualpage(1); % P8 H: C5 n" z6 D2 X
/* clean up */ 7 Y! `$ Q- G s6 o) s. d
getch(); 2 t* e: M" j8 s5 e8 q0 R g5 ~
closegraph(); ' m& e5 d( e$ F: c3 W" y7 l! e
return 0; * T) l" y8 G' }
} 
* Z; J) k6 s: v0 `
& P( L* E. d& ^7 y7 Q& H8 `0 r) h0 M' a% H" e, s0 _# `; q
函数名: setwritemode [7 G( m% J, a
功能: 设置图形方式下画线的输出模式 , w7 ?% g/ P9 ]/ ^7 I. l* W
用法: void far setwritemode(int mode);
5 F: W5 [) F0 ]) ~/ ^- q8 X [4 o程序例: 7 B0 J: ^7 x) D x1 [# H$ Z
#include <GRAPHICS.H>* G; H' \8 W7 [3 H9 n
#include <STDLIB.H>
- Y& w6 B! q% \. l3 k#include <STDIO.H>
) B3 m/ T! U7 @/ O#include <CONIO.H>5 G; C* t, n: q" X/ n* d
int main() % V& [+ ]" V, U$ W) b0 y
{ 3 q' s' K3 e# ]: I
/* request auto detection */ 6 f- w2 U" X% r
int gdriver = DETECT, gmode, errorcode;
; r1 n, R6 u* s- I( [# [. t) Y1 }int xmax, ymax; 
( r+ k A- G8 H+ G/* initialize graphics and local variables */ $ ^( {& r& G, m+ P+ Y
initgraph(&gdriver, &gmode, ""); 
/ h3 Z0 }$ J- e6 M# ^/* read result of initialization */ 7 j4 U: m8 @# `" a+ v* ^6 S
errorcode = graphresult(); 1 a0 x! d& k) R- \$ u
if (errorcode != grOk) /* an error occurred */
7 w" _3 ~9 B7 I' D' v1 z% v) C% p3 A{
& l; V- q, i+ Jprintf("Graphics error: %s\n", grapherrormsg(errorcode));
8 R4 R% B, e( D. F" bprintf("Press any key to halt:");
( b |% l" T& }# _getch(); ( f" |' c, E- |5 u
exit(1); /* terminate with an error code */
+ t5 t9 W6 s0 d8 x# _2 N% N} 
5 W" d9 T" P; L8 x' _6 A1 Uxmax = getmaxx(); 9 t! c Z1 h9 y C D0 N0 T* X( b
ymax = getmaxy(); 
7 f; F9 K. ?& s1 ^3 N% U ^/ h/* select XOR drawing mode */
 Q+ s* ~# [, C! i* zsetwritemode(XOR_PUT); % D0 _4 d. [( ]
/* draw a line */
6 F( l2 p7 n! b9 S5 ]9 K2 ^line(0, 0, xmax, ymax);
6 k. H6 R3 m8 Wgetch(); ; s9 P6 [( r& f W# N; S7 t
/* erase the line by drawing over it */
9 R6 C7 m' l& v b, }: l. ?* pline(0, 0, xmax, ymax); 9 C/ I! O# N$ m% v
getch(); 
# n, y4 z$ X8 \+ ~. b/* select overwrite drawing mode */ 5 F, g6 ]) R' B' ~4 x4 Y* ?
setwritemode(COPY_PUT); 
: h. |9 `! X* A y# [' |- N/* draw a line */ 9 R+ R+ W, s! c. U7 G
line(0, 0, xmax, ymax); ; P1 [' P4 z/ ]5 u$ Q. R# r
/* clean up */
8 L8 n; I# o9 u9 Zgetch();
0 B% R4 H5 {& S3 v& G( [closegraph();
+ A" D! W) X- |$ oreturn 0;
 P* y/ _; H: I7 j8 [( H}
. I3 C! C2 T( O. D5 j. w3 u& G P, `0 r- p& _# `2 L! X1 N. g$ k' t

7 e: R4 b# G$ ]! Y* [* g L函数名: signal # P A N' b7 b% K$ q/ f
功能: 设置某一信号的对应动作
5 m2 U( j. C7 _用法: int signal(int sig, sigfun fname); 6 e9 @9 g: j+ S1 O7 y
程序例: 7 H( e" `( p, c* M9 q
/* This example installs a signal handler routine for SIGFPE,
& i% }! u' E: w/ g+ ^/ p, {catches an integer overflow condition, makes an adjustment
5 F# _6 U3 Y F, Y0 M/ P+ e6 }to AX register, and returns. This example program MAY cause 9 x" J3 Y, S8 m2 A; a* b: _; v
your computer to crash, and will produce runtime errors 6 F$ e0 q. N4 K. P, c6 l# O( d' q
depending on which memory model is used. ! |' f9 F n0 ~) k
*/ 
2 k; D+ }& @3 s; t0 d8 z) L#pragma inline * @3 x0 K1 i' P/ v6 h' z U
#include <STDIO.H>
) P% ^# v" _ X' G" i" M* M* R#include <SIGNAL.H>2 ~2 p, X7 A5 c4 f3 f9 J& Y) T
void Catcher(int sig, int type, int *reglist)
) @- `' P4 m" [ R5 F{ 6 V! ~& K- E6 ]1 f2 p
printf("Caught it!\n"); ; k1 Y% S1 Q4 x( g% q, z& s
*(reglist + 8) = 3; /* make return AX = 3 */
4 W$ [, Q3 ]4 l) s} 
9 _9 x2 x4 \, |( mint main(void) % b+ J' I! _# g. {6 e9 B
{ . [- n) j2 H/ {) X5 [: A1 ?5 O
signal(SIGFPE, Catcher);
2 D4 S' m- j8 I2 A! Y9 }% |. C0 [7 sasm mov ax,07FFFH /* AX = 32767 */ 4 f1 ?3 O4 ?: F& o" _. x" S. _
asm inc ax /* cause overflow */ m- r( T" A& w0 L) n% O7 b* Z
asm into /* activate handler */ 
" ?/ g2 A& N' I* M, @% }( K$ \/* The handler set AX to 3 on return. If that hadn't happened,
5 R" f p6 T6 e j6 R6 zthere would have been another exception when the next 'into' $ w. I, T, L0 K9 S' r( g
was executed after the 'dec' instruction. */ # h/ p; @& B* G& M
asm dec ax /* no overflow now */ 9 i, b! a4 }! A# h- g. h
asm into /* doesn't activate */
0 [1 j& F' k( areturn 0;
0 o |2 n7 C/ f5 o( Y v$ o} # r/ F; Q- }; A' }

5 O' r( I- q. I" k% K7 H) Y
# j% E8 U0 q; ]4 V5 L1 H$ d; |" H* g( Q/ ?6 k X. F
函数名: sin . {) K% w- G; Z J
功能: 正弦函数 & l5 F1 l' \0 g
用法: double sin(double x); ; E$ \ z, h, c% G0 Q
程序例: 
8 K" x5 O+ f& s5 s& R#include <STDIO.H>
- @& O/ k1 X4 H#include <MATH.H>; U# F6 e- B, }0 O/ i! G2 `5 h, l& h
int main(void)
5 A, P( k/ ^7 f$ v{
' e. n Z' c5 ?double result, x = 0.5; ; Q2 Z& W( r7 _/ s
result = sin(x);
& `, \& b$ p u9 ^: d* O' c+ Vprintf("The sin() of %lf is %lf\n", x, result);
, P3 ~) W' E* d: ]9 X: J( Areturn 0;
* Q7 e* ~& l9 }1 V% I8 I. e7 `}
' S% v; r$ a. o
3 w5 F4 K) C L& _. |) v- @! j8 v6 I* ~
函数名: sinh 
 ~) T# X" u" \# H D2 M功能: 双曲正弦函数 / H$ o# H# X+ \. j$ ?/ V: z
用法: double sinh(double x);
5 H0 r0 {# ~5 [" d, s程序例: : E0 E5 p! S) E9 c. c# J
#include <STDIO.H>- I4 v' P% X2 Y; ~( ?
#include <MATH.H>9 e% N$ L4 l; A1 s
int main(void)
6 x2 E8 D8 g& z{
$ e* f7 g( p& gdouble result, x = 0.5; 
& H( Y. ?9 i9 ~+ f( D$ h% dresult = sinh(x);
7 u! m. v% K5 Q4 Z" N- M8 aprintf("The hyperbolic sin() of %lf is %lf\n", x, result);
# N; t: c. D& q# D6 H% kreturn 0; 1 a0 W0 N% O5 l- Q( m% M
}
. M* F: G- f3 P2 X5 n
* [; i6 l: h2 v& b8 ~$ s7 L; W J- J
+ }# z) f+ i; ^. b: m9 t: _ x
1 o& F j1 @) B5 N1 P+ a. ^函数名: sleep 
# k1 v, o( F0 g3 m+ y功能: 执行挂起一段时间 0 G, F. @- N. q: l$ Q
用法: unsigned sleep(unsigned seconds);
9 k2 \6 j1 B4 J8 |程序例: 
' A: |+ r4 g0 e5 M8 m$ P2 V) D#include <DOS.H>6 e( a4 W( g% n) K- ~ k
#include <STDIO.H>. f! F5 Z8 r% W* C) i! K E
int main(void)
1 Z. y% Z, H4 `/ R{
+ u3 r [7 ]/ Q; r% m+ {int i; 7 L% h( k! ?. j/ F; e {$ t- C: w1 ^1 {
for (i=1; i<5; i++) ! ^! A8 A$ Z/ g: y8 y$ n7 |
{
) H: v V) q! [% o- @5 _printf("Sleeping for %d seconds\n", i);
- o8 Y% p9 a6 A3 {, J. hsleep(i); 5 g0 s; m+ v5 ~" K8 L
}
: ~1 Q2 I) N: A1 q- W7 s/ Ereturn 0; / E) m2 w2 M( w/ @; b6 f- Y
}
 [- q' d7 L0 o% F. q/ C+ s
' S" X2 D' j& T8 t/ \6 O9 `1 O
* S, Q! A$ e) y, F- y# y" C9 H! _# F
8 t/ q* H! `6 h/ c$ ~* O函数名: sopen 5 s( S3 L, \! E" e3 ?4 B1 _+ _
功能: 打开一共享文件
4 B& p5 J& N. H1 ?1 W9 G: F用法: int sopen(char *pathname, int access, int shflag, int permiss); " i$ l, _$ F8 D: D2 D
程序例: 3 B/ u: o% Z/ D8 W0 @- r
#include <IO.H>, C: Y3 G& w+ R! _ A8 j: M
#include <FCNTL.H>3 V" a3 g* Y2 t3 E
#include <SYS\STAT.H>
+ E' K q/ ]6 ^3 k( L/ z4 J d#include <PROCESS.H>
3 C9 n8 U6 @/ ]- }$ d#include <SHARE.H>
/ Q3 k- _6 z2 r5 A#include <STDIO.H> K2 o% E5 _% ^9 B8 @2 ]2 k/ w
int main(void) 8 w8 S( u7 @ }. t0 }' o: y
{ ) K5 d' F' P+ U" E% o9 A
int handle; . h% G" [; j6 i3 O) D5 g
int status; 
1 }2 G9 u+ @5 }( n( {( P8 e5 _2 t4 Yhandle = sopen("c:\\autoexec.bat", O_RDONLY, SH_DENYNO, S_IREAD); 
' @# e) _. r1 _! Gif (!handle) 1 t$ G# d, E( D# ~# |) ]
{ & g6 c4 u( ? z: z7 r" Y! @2 X0 L( w
printf("sopen failed\n");
1 U h4 {/ K3 cexit(1);
/ [6 t; u9 v( f. }8 y+ i} % M; S+ p. }; l
status = access("c:\\autoexec.bat", 6); 2 @- [4 ^' [# A" k6 z+ Z
if (status == 0)
; u/ ^5 d: T' wprintf("read/write access allowed\n");
8 l4 Z* B2 b# j# aelse * p3 X7 ?. t7 Y# s, ]5 R8 u) ~
printf("read/write access not allowed\n"); ; J, v6 U+ j) F, O" N0 c
close(handle);
6 c6 g: L& P0 c" y S3 ~return 0;
3 c* G0 V/ S3 I8 G} 2 Y8 q. v* S# B/ I1 R# k7 f/ B

/ q* @# _% X$ l
" c& T4 f' `; b9 K1 k( u
 }5 q5 R+ d: A" o' `) _( Z函数名: sound : M! u3 h4 {, L5 h& R; h l. }- ]
功能: 以指定频率打开PC扬声器
+ x& r- [7 R" x) M. \) w, W: ?用法: void sound(unsigned frequency);
* _! X" g( P( C/ [9 q程序例: 1 w% b0 Q, c/ M+ p
/* Emits a 7-Hz tone for 10 seconds.
+ v. R6 Q5 s' m3 j+ q$ zYour PC may not be able to emit a 7-Hz tone. */ # O" D* j% z1 b8 Y
#include <DOS.H>7 U$ f7 K# m0 S9 Y6 w% ^2 M8 C
int main(void)
0 l' H# Q4 w k. f: G{
1 a, G) g# v& a9 D+ }3 ssound(7); 4 z: Z) _) h, f
delay(10000);
6 I) R1 J. B; ]nosound(); 1 e9 I5 j' g# }% l( F! P
return 0; : j x4 Z4 F! i$ z6 m( H
} 
/ s$ t3 a8 v+ T L( G+ z* `/ R- _$ |1 R" g' [

, d6 U3 c8 v2 S
1 y. ^( I7 ]6 m Y. c2 [函数名: spawnl ( o0 m5 r! S [) O$ F0 v1 K- I) F
功能: 创建并运行子程序
, Y! p. `! C3 E! H9 m% q4 c用法: int spawnl(int mode, char *pathname, char *arg0, + z9 F# S5 C# n2 g
arg1, ... argn, NULL);
8 _* p, Y4 E/ ^' m0 U8 u程序例: 6 ]! i. k" i0 k! y6 a: j
#include <PROCESS.H>+ R% d! B; M2 p; C$ C# M9 p
#include <STDIO.H>9 b, F2 _2 {# ~5 M3 A( Z- {
#include <CONIO.H>
7 t. g. X- F+ ?! Fint main(void) + v$ a6 f' p9 B, w- E% l$ m! ~6 X
{
; Y- v4 k: ?% F- ~ S" z8 d( u" Dint result; 
7 m o% ?7 b6 n: F: ]- ~' s8 ~- y2 |clrscr(); ; U: [% X' I3 y# U) j$ W: n4 N
result = spawnl(P_WAIT, "tcc.exe", NULL);
( [ g( h2 W7 q$ z0 p" u7 |2 oif (result == -1) $ z( [0 W1 E O r8 o7 k! V
{
6 a. r" \9 V. ]$ R* I* Bperror("Error from spawnl"); 4 M! [3 {& k4 l% c. ~2 B9 a
exit(1); 9 N' o# E0 k# z/ L
} + C! n' v$ \1 @/ h+ k4 D( a
return 0; $ r3 @: G' j( V1 B) v1 \
}
8 b* X* A& T' A# R" r! m: @; ~" x3 `6 v0 W
2 q0 ~' w# C: i2 Z3 E
函数名: spawnle 
1 q8 N0 Q7 ~' O8 b h功能: 创建并运行子程序
. w% V0 ~' Y6 h1 v7 [2 j用法: int spawnle(int mode, char *pathname, char *arg0,
2 b: t/ E. I! A8 J' h% E3 Y; Karg1,..., argn, NULL);
$ t9 O: A$ |. p% A: r; H) g3 L: o程序例: 
, t* V& ]) `3 x$ \, U$ C4 l$ R' ^/* spawnle() example */ 
2 z2 b P2 K3 o1 v @5 z#include <PROCESS.H>2 m/ F/ A- V7 s: F- k
#include <STDIO.H>: i" ?2 k- v7 s ?
#include <CONIO.H>: j, {, S5 I7 [) X- f2 u. C% l
int main(void) w0 X4 H1 u! ^9 A" Z
{
9 [) J6 e. B/ Eint result; 
 `# y3 d3 z4 w. T7 `5 o. Dclrscr(); 9 q4 V" O; n$ H5 ~
result = spawnle(P_WAIT, "tcc.exe", NULL, NULL);
6 @/ a1 P) ` r8 L: [if (result == -1) , i6 M% v! t9 k4 V+ t" O/ s
{
* \% d( a. Z X6 zperror("Error from spawnle");
! @- K$ ^% E( b( Z8 N7 t% L( wexit(1);
' I/ b# p/ d# W6 m( P}
9 o3 w. ^# I. X {, M* ~1 [return 0; 5 o. c+ E+ n2 x- _, C! P) C
}
- h" x. M5 S" A8 Y1 G* k- C: P+ I- J8 d
( @5 f r- T4 u5 w2 [' s; N- |7 V+ O1 ?& p0 [8 x' k: O, c
: i9 H2 m4 G7 Z2 Z, I
函数名: sprintf / X+ B) T4 }9 N$ ]$ F
功能: 送格式化输出到字符串中 # T% G$ _+ r z, i
用法: int sprintf(char *string, char *farmat [,argument,...]);
" \% u' E$ ~, l程序例: 
7 R+ z7 L p1 H+ q4 b8 L#include <STDIO.H>
8 F8 _8 Y8 g( |# S8 v; V6 c#include <MATH.H>
. n% }& r. p' |int main(void)
7 u8 S; |# r3 t# @{
! g! W8 S; M3 n' A T- G9 f; x- zchar buffer[80]; 
* b# i* `$ {1 B; O Lsprintf(buffer, "An approximation of Pi is %f\n", M_PI);
! |# ~4 o1 G5 l) L% a P Yputs(buffer);
8 f+ d$ A0 V0 u! ?2 Jreturn 0;
9 h/ V6 m4 w1 z6 `9 }} , O- Y: I9 ]. c6 n% F
( _) V2 q9 i& p& S* E/ ^/ p. {

: Y- P6 g( f! ~函数名: sqrt 
# ]+ \0 D' |7 M$ y功能: 计算平方根 x$ ~2 `+ b: A! h
用法: double sqrt(double x); & ?8 B# l( P8 v; L) w1 |9 t
程序例: 4 H$ i% _5 |8 H p6 U5 B& Y
#include <MATH.H># F6 a/ \5 {2 O1 U
#include <STDIO.H>
2 ]" R5 Y6 e j" }, D* cint main(void)
. Z. Z) b; Q+ f e/ U{
2 i( F' i! ~$ g! q9 [double x = 4.0, result; & L( Z* r4 t5 k: E2 @
result = sqrt(x);
" ~- }2 ~& ]! cprintf("The square root of %lf is %lf\n", x, result); 3 u9 ~: m4 [, u2 k2 V* w1 v0 G9 I
return 0;
0 J0 q7 U! f5 }5 H3 C: G9 z1 n0 G; M}
" p }0 C+ C6 i! Z4 V G. A0 z5 ?( e, @0 A6 Y% z3 T# G
函数名: srand 1 \; K- l; D( p! V& n
功能: 初始化随机数发生器 2 i. ~ Y( `+ J( j+ @4 X6 j
用法: void srand(unsigned seed);
, R9 t/ R: ^' {程序例: 
$ f% F) k1 K: ]8 I' P+ I$ L! k#include <STDLIB.H>1 J7 J5 ?( N4 t( H) {
#include <STDIO.H>
# d! n! L6 c( F/ `% `#include <TIME.H>- z+ c6 l0 n6 z+ J
int main(void) - T1 c, d9 i. K
{ : ~- X, g! Y# T- L
int i;
3 @$ [6 I0 g' I# w9 X5 utime_t t; 
. m. b9 R9 }% c! p5 isrand((unsigned) time(&t));
! U& S7 \) w* n3 G8 V, Y+ mprintf("Ten random numbers from 0 to 99\n\n");
5 b6 V. i6 X+ }/ R+ Ifor(i=0; i<10; i++)
: @4 V% g! }8 Z5 K Q: @7 Fprintf("%d\n", rand() % 100);
: K8 \3 x* g6 Vreturn 0; - e7 l$ a w5 T% H8 @
} y* `/ t) r- ^0 {# G: B8 [, H0 S
2 [" D4 G; p: `' Q W8 n2 l

; ~' S7 L9 ]9 o3 t函数名: sscanf ! R1 E/ h/ r6 o0 F1 Y; q
功能: 执行从字符串中的格式化输入
$ y1 M) ?% z X用法: int sscanf(char *string, char *format[,argument,...]); : k2 }0 a, t( t2 f, }/ A+ |, N
程序例: & W3 m/ [3 ~8 s2 L
#include <STDIO.H>* u# F+ g ?4 ]3 }, {1 K ^) T# {
#include <CONIO.H>' X. { [# }- |' V' D2 _; _
int main(void) 9 j0 \3 g, X( Y& P8 A) R0 s2 f" j
{
 T7 ?+ Y; \- h1 |char label[20]; 9 T- w, T: I+ z
char name[20];
9 [" C0 L$ q3 V9 X r8 s& E2 Lint entries = 0; & `+ I& R# I2 v
int loop, age;
7 V) U& C9 V# m; A. [ y+ [double salary; / V; R$ x% q1 B7 C; J
struct Entry_struct - T. }' S. q3 O) Z1 Q" o. X
{ ! v6 a" I+ ~2 W+ V+ W
char name[20];
6 U6 ?. j" N" W( d) Vint age; 5 `9 a3 `$ I1 x4 f4 |& T3 U6 s F( R% V! |
float salary;
! D8 O% h- D) e0 T} entry[20]; 
5 d' h3 k6 f) f( U ]$ N& A/* Input a label as a string of characters restricting to 20 characters */
 H0 o& U9 E% C; e0 f# y& B* b1 Xprintf("\n\nPlease enter a label for the chart: "); ) m/ m0 O- L" T1 t
scanf("%20s", label);
# n5 u5 f R- Tfflush(stdin); /* flush the input stream in case of bad input */ C' S5 Z+ L' j& U8 B" A
/* Input number of entries as an integer */
1 Q/ w2 k% ~6 g8 ^' N, aprintf("How many entries will there be? (less than 20) ");
; {/ {( B- d% k0 b* E1 B4 N) Rscanf("%d", &entries); . u! g' L" i7 O- k
fflush(stdin); /* flush the input stream in case of bad input */ 5 o9 Z6 L* W& Y0 _: X' b
/* input a name restricting input to only letters upper or lower case */ , J) F( _# }/ T/ R: L! A
for (loop=0;loop<ENTRIES;++LOOP) 8 v# k6 k" H9 w$ J
{
0 N7 ]) l B, ^. V7 `& Jprintf("Entry %d\n", loop);
 y$ e0 U0 r$ ^& V9 P7 ^printf(" Name : ");
% e2 U, s+ D1 C. Mscanf("%[A-Za-z]", entry[loop].name);
, L( L$ i* p l6 V: Qfflush(stdin); /* flush the input stream in case of bad input */ 
9 z# K/ o0 M6 K7 {/* input an age as an integer */
( P' t8 D/ D& U8 l( h3 r; `# pprintf(" Age : ");
8 r+ b% N, Q7 W, o% `1 ^ {scanf("%d", &entry[loop].age);
. _! a" T5 g% G$ i" V, J4 D# S# U% Vfflush(stdin); /* flush the input stream in case of bad input */ ' C1 q6 m1 S& \" G# \% V
/* input a salary as a float */
7 K7 N5 [0 w+ m% u$ J( ~, Rprintf(" Salary : ");
$ a: T9 l9 C# ?+ rscanf("%f", &entry[loop].salary); 4 Y7 \& } |8 g4 ?( m- u5 ]
fflush(stdin); /* flush the input stream in case of bad input */ ' A- [* [; w2 ^- N' T
} ; x4 b9 h/ I3 [: M7 @' [1 j N( N; f
/* Input a name, age and salary as a string, integer, and double */
2 ?$ m0 p2 z0 [printf("\nPlease enter your name, age and salary\n");
' V) c+ t+ A1 {: Cscanf("%20s %d %lf", name, &age, &salary);
% c4 g9 D6 v H! m1 h3 @5 x$ @. n: j1 T1 z
/* Print out the data that was input */ 4 [; E+ u! s# L$ p
printf("\n\nTable %s\n",label); 3 Q# B& e/ Y9 I. O5 x% K
printf("Compiled by %s age %d $%15.2lf\n", name, age, salary);
: n& V; {" |- s% N5 Q" w9 Fprintf("-----------------------------------------------------\n"); : z8 D/ K ?2 ]0 {
for (loop=0;loop<ENTRIES;++LOOP) 8 n. j4 C' r. Z! f+ D
printf("%4d | %-20s | %5d | %15.2lf\n", ; E. S+ k+ I4 |# p5 P
loop + 1,
9 b; W7 I, d* J) s% x/ v5 ?7 A# Jentry[loop].name, - P! g% Z) \# \. b" K& g' f2 J
entry[loop].age,
* ?9 ] Q4 P% W3 Mentry[loop].salary); ; v. }1 L- A4 T7 O$ a
printf("-----------------------------------------------------\n");
' b& d0 y% x `3 p3 @return 0;
4 d" I+ R& x# {; Q: x} ! I: b3 Z# R o5 [# z1 F
6 ]5 ?( ^+ n( d! I+ |4 C; v5 M

) L- e4 w! [0 i# t* q& o函数名: stat 
( O" q" ~; _0 x( q4 `3 w% \功能: 读取打开文件信息 0 N7 c* _. S1 w( P& v
用法: int stat(char *pathname, struct stat *buff); 5 R* x+ w5 c3 f" R8 ?/ ^' e1 Z" x
程序例: 3 V2 m" s0 Z$ g
#include <SYS\STAT.H>; v M5 B& c1 d: O# R5 l. R, L
#include <STDIO.H>5 {) p$ J; O& r; ?' H' e
#include <TIME.H>& k- N |" A, `$ C: B
#define FILENAME "TEST.$$$" 
( t& \9 L5 { R4 s+ ?2 cint main(void) : q. \! N! h( d; E% ]: h, T$ l+ o" Y2 p
{
; w7 d% M4 o7 W% xstruct stat statbuf;
 `1 Z: C$ |; X. @FILE *stream; 
6 {+ z( d( b, }/* open a file for update */
1 L! t$ Z+ j4 I. |% q) W3 u. _if ((stream = fopen(FILENAME, "w+")) == NULL)
; S6 b1 y+ {5 x( [" m. [( h C{
3 T x; c- M# H' t& f. X1 @- sfprintf(stderr, "Cannot open output file.\n"); ( t9 t1 U! \3 ^; f9 [" }+ I3 y
return(1);
/ P) T' O) s; A* y8 j: c9 o: A} 
 c9 z: W& [/ k/* get information about the file */
' |! r, P' T0 A: }stat(FILENAME, &statbuf); 5 U5 r. \, C0 t: n" C/ `' u: W' `
fclose(stream); ( q7 [( J; f; O5 R$ y
/* display the information returned */ & I: P9 g4 m d' d3 ^- T
if (statbuf.st_mode & S_IFCHR)
* Y' ?6 _' b [+ z G" Zprintf("Handle refers to a device.\n"); / B8 x# Y4 ^2 o9 z/ F- }2 X- \
if (statbuf.st_mode & S_IFREG) 5 `& T2 k: ?8 N' A
printf("Handle refers to an ordinary file.\n"); . A F: v7 ]8 E) E4 C1 J; G5 j
if (statbuf.st_mode & S_IREAD)
) N7 g. y+ S' g' b! D7 I( m" T" J& jprintf("User has read permission on file.\n");
, h. W# |$ U* B6 d* A! j4 fif (statbuf.st_mode & S_IWRITE)
1 V4 C# |3 j+ C6 H* k sprintf("User has write permission on file.\n"); # x% L" S/ K8 T5 c; q
printf("Drive letter of file: %c\n", 'A'+statbuf.st_dev);
4 k+ u7 j2 n; y5 v9 W$ sprintf("Size of file in bytes: %ld\n", statbuf.st_size);
2 `" j& L* ]0 L: |9 o# Lprintf("Time file last opened: %s\n", ctime(&statbuf.st_ctime));
: V" U7 P2 o' s. U Y' Z2 v4 O5 \. Treturn 0;
: N" H9 u5 P$ m4 f}
+ k# o, m' M" G7 \: l- w1 }0 u' C3 \
 m& l4 ~ _9 w8 J( h6 Y; K

4 X/ o( f/ Q, u& Q* g; P9 D+ E函数名: _status87 " {: E! [9 d- X) `4 E
功能: 取浮点状态 1 ^* R6 I/ F- O7 J! k8 F' ?
用法: unsigned int _status87(void); 1 X9 a/ k$ D% |, o
程序例: , m& H3 f; \: ]4 o
#include <STDIO.H>; B Z% e- S+ ^6 x: R
#include <FLOAT.H>
2 Q6 J4 m. ?) F/ M* f, B# h; J' Cint main(void) - K' J* F( h0 l8 g. j
{
% J. c3 T* [5 G. E# [% N9 _% j. `float x; 9 y2 z9 B g2 ^$ G
double y = 1.5e-100; 
; U4 {$ u a4 g1 Hprintf("Status 87 before error: %x\n", _status87()); 3 D X E' S% w( F, r' N, B% D
x = y; /* <-- force an error to occur */ / a6 q0 F. }% c+ g
y = x; , p' M5 @' d5 ~( O
printf("Status 87 after error : %x\n", _status87());
( [: ?* j0 ~5 G8 M- rreturn 0;
6 J* R( U$ v$ W$ j; Y7 I/ e}
4 x1 H+ J9 C% t) j/ @+ w4 }2 j8 {( o1 }1 |: v8 b, r! T5 r
( b) i+ u4 ]7 t2 _$ _+ V
函数名: stime 
: F1 T3 s) ]4 A% U) x& F功能: 设置时间
9 K/ Q; |% p+ E/ ^5 I+ e K1 Z5 L用法: int stime(long *tp);
2 W# L! j/ G3 j7 S1 ~( a程序例: 
8 V7 L8 P, A4 m+ k7 j% @% `+ O6 k#include <STDIO.H>
' ^, i9 @& ]1 A#include <TIME.H>
0 S* J' D6 p( Z" Y5 o#include <DOS.H>4 Q3 _: ]5 M' j
int main(void) N. |* ^" n8 f
{
 o4 u) [* H7 l" l6 dtime_t t; : u7 k- e+ f+ L1 p
struct tm *area; 
1 C8 D6 k: I ~: b! i3 Bt = time(NULL);
! B, a% h7 x. ]1 H- f5 Larea = localtime(&t);
# K% \& p" h& m, e( h( ^printf("Number of seconds since 1/1/1970 is: %ld\n", t); $ ~$ _9 J3 {& _
printf("Local time is: %s", asctime(area)); % J% D4 v' m8 o
t++;
* h, ?/ X, G/ C/ K4 Karea = localtime(&t); 7 w( d; W. K& G, M, M \; i# }+ ~
printf("Add a second: %s", asctime(area)); 1 s3 l5 H' z' k/ X+ C# [/ W
t += 60; . T' X6 m; q. k/ i1 F) I" X
area = localtime(&t);
; a9 r) P1 l; _- A9 rprintf("Add a minute: %s", asctime(area)); ) G! _3 A& B" _* z/ z- o$ n
t += 3600; 9 T8 z0 K$ U, d
area = localtime(&t); 8 w8 ^1 p# k& [7 J" Q0 A
printf("Add an hour: %s", asctime(area)); % N( v7 E9 n" w0 f6 w- |2 b' c
t += 86400L; ; F- l4 O: ~/ w$ F
area = localtime(&t);
$ _$ C( ~; e n+ ^$ h& z: Oprintf("Add a day: %s", asctime(area)); ; {, Z" n$ m" T' K) C8 [% r
t += 2592000L;
' a; X, B0 m* a6 C+ W' Y8 Darea = localtime(&t); % c; r5 } w+ @$ j* g4 W8 ^
printf("Add a month: %s", asctime(area)); 
1 {3 t0 n/ F$ U jt += 31536000L;
2 R- R" Q L6 n+ q5 G7 Narea = localtime(&t);
' I0 w+ r2 {3 n# tprintf("Add a year: %s", asctime(area)); ) ~- Z9 i0 j& v: W, \. D8 S
return 0;
% g6 q( ?: d6 S' b# j" |4 P( G1 S} 
+ i+ Z: A+ g2 {* M9 X- E" H7 S& q& f2 j, I. \

7 ^. f# |( F' X
 j! n$ k( y7 A; B函数名: stpcpy 
& [* P3 d) G4 g+ ~/ f功能: 拷贝一个字符串到另一个
/ q. k+ ?7 X( s/ p& u7 X8 c* a0 a& T用法: char *stpcpy(char *destin, char *source);
, A- Y7 N& I1 W9 y程序例: 
, F3 X& T! S3 I9 q#include <STDIO.H>
8 n% Q. J r% W O* c9 S#include <STRING.H>$ m3 q! |/ |. v, V3 F& I
int main(void)
, Y) j: v* t i3 [- W{
/ m- T, r9 P0 |char string[10]; ) i8 ?/ u0 a' v6 c, w1 q' P' P
char *str1 = "abcdefghi"; # v( t* r! A; Z3 k
stpcpy(string, str1); 0 \5 E; E9 A& Y
printf("%s\n", string); * N1 p# D1 ?: E$ w6 k+ M+ N! s% f
return 0; 4 X8 d, ~ |& s5 K4 M$ t
}
4 \; d& x" ^# x$ b
' w' `4 v/ v' Y: w
- I* a3 Z9 P/ Q7 N1 O7 [/ X+ H" W1 v* X. |+ B. d/ Q7 [% i' Y
函数名: strcat 
* ?0 \% Q2 U6 s功能: 字符串拼接函数 ) K- w4 G; T) U5 g; d# E6 J1 Z" l
用法: char *strcat(char *destin, char *source);
& G3 P" p6 z* M4 ^4 r5 s程序例: 9 {/ S: U! O7 i; l R( [
#include <STRING.H>8 C1 P v8 F. S o9 G3 K s) T# {: q
#include <STDIO.H>
- M* X6 T& @* ~4 L, c( v( G3 bint main(void)
5 W& f. q3 u1 q& ?: U. _, g{ + z4 l* g7 N0 d+ m% p/ {
char destination[25];
7 f1 J2 p/ O$ `. V0 xchar *blank = " ", *c = "C++", *Borland = "Borland"; 0 b4 _& D+ ]" u2 ?" {& S
strcpy(destination, Borland);
8 u1 b5 L; Q- w. p, u3 ]4 Gstrcat(destination, blank); 3 f& U0 s! \* r0 S( P9 Q; {
strcat(destination, c); 
' K: [7 x# r- x- D9 M, qprintf("%s\n", destination); 0 T a+ r8 P; }
return 0; / b6 A; w' u8 B9 q2 p. ~9 m
}
' F# _; T- E( B: [2 C+ N) l( x: `5 w5 ?) e, R( h

- b+ q# g/ ?: A4 B9 Y0 N! x: G+ g' d7 t2 m; _" P/ ]( D' D; _( S
函数名: strchr 
, m# e! |0 U. |: a2 M8 {0 h功能: 在一个串中查找给定字符的第一个匹配之处\
6 X) ?7 Y: K& [! Z/ w用法: char *strchr(char *str, char c); & ^- ^( n9 `5 V1 ^
程序例: - G$ {' E% [' Y8 ]" G) Z( g$ A+ x
#include <STRING.H>4 Z" v* m( B* Y8 {
#include <STDIO.H>
$ |8 j! m1 Q& M! z7 M) e9 ?! bint main(void)
9 Y/ i) Z8 V# c{ ) I6 w, C( W' ^! R, [! t
char string[15]; ! n( L3 _ h7 ?
char *ptr, c = 'r'; 
$ \8 c e+ }! n4 U0 S, g6 Ostrcpy(string, "This is a string");
+ A. A% o2 v. I$ r# qptr = strchr(string, c);
4 M2 Z5 p X5 L- ?8 c/ Kif (ptr) 1 f$ @; L$ g0 Y) b
printf("The character %c is at position: %d\n", c, ptr-string); ' c4 n9 i; K% B- t# k( X/ t7 P* E
else 1 F4 h M; m1 S1 s
printf("The character was not found\n");
. p( u9 m5 Y! L) o: nreturn 0; % I- a- B' l6 ^4 t
}
! L+ ~, T6 k, m7 A0 z) ?/ c
6 g. i5 @$ a2 Z8 o1 S& F1 D3 ?. }/ a1 m ~9 r4 c

# c% M' e6 e7 E8 v; E函数名: strcmp 0 ^! G, o9 Z7 c4 `
功能: 串比较 ' t$ F: t1 N5 C. `- {1 C j9 g) s
用法: int strcmp(char *str1, char *str2);
$ A$ w! b9 e# n# d+ G: a7 A程序例: 
/ k. O8 Q6 u+ p/ e' |% I" U7 R) k4 a#include <STRING.H>
, z$ }& D/ I" h/ H. x, b#include <STDIO.H>% u, \1 H X2 u |9 b/ H
int main(void) # I# d7 L( X, I( l9 e# ?
{ " L! H d$ t& s# N# }7 m% m: q
char *buf1 = "aaa", *buf2 = "bbb", *buf3 = "ccc"; , i3 m F; r) y" e! Z
int ptr; 6 M: ?5 z7 o. X" j; B7 j9 v
ptr = strcmp(buf2, buf1); 6 C5 L: \5 o0 Z/ q1 o/ ~
if (ptr > 0) 0 J7 ~8 M( `- s3 Z( h1 t
printf("buffer 2 is greater than buffer 1\n");
) F2 \3 B0 u+ ^$ |- A- m! Welse $ m7 O: E* i4 p% m: K
printf("buffer 2 is less than buffer 1\n"); ' \( Z$ C) a! w- F1 |) p4 w
ptr = strcmp(buf2, buf3);
' Z/ g* j6 [0 O" k2 eif (ptr > 0) 3 W) g4 b) n$ E( d' x
printf("buffer 2 is greater than buffer 3\n"); & i# }2 v9 V/ Z/ m- T
else
 Y; |/ o9 ?2 T7 r% a" [( i7 Bprintf("buffer 2 is less than buffer 3\n"); 
- @$ T! s+ @" y* q, J7 b, Nreturn 0; % [; f" H. x! Q M: p# R
}
+ }+ I6 v0 e- y
, p6 z* f O3 R1 C$ @8 ^) H
* P2 w" @0 _3 @. J
6 w6 Z- {, c5 }$ V函数名: strncmpi . U4 H: R% x! O9 d& w4 C# O+ `
功能: 将一个串中的一部分与另一个串比较, 不管大小写 + z0 [) S B: j0 \! j* L
用法: int strncmpi(char *str1, char *str2, unsigned maxlen); 4 D5 @3 l9 f: `# b; W/ @) {: w: ]
程序例: 
* g. D" `5 w, [#include <STRING.H>
8 \# e4 b( r1 ]. v4 s8 |3 b#include <STDIO.H>
" [8 b' V" V5 L0 s f( K* p8 Jint main(void) % _: P$ c1 k" v; H
{ 9 F" A0 U3 [6 D; Z1 D
char *buf1 = "BBB", *buf2 = "bbb";
" d" v& p* O. bint ptr; ( y- z/ e9 T/ H* f ]- ]' W
ptr = strcmpi(buf2, buf1); $ v4 x/ @% i+ |' L1 S' F" d( M9 T
if (ptr > 0) ( J1 S) n, [5 h% b! [/ T2 }+ J; X
printf("buffer 2 is greater than buffer 1\n"); 4 X$ p j0 y' P) v- H% {0 C
if (ptr < 0)
- c4 |+ P, R; yprintf("buffer 2 is less than buffer 1\n"); 1 N- V6 v; Y* \ J }" z
if (ptr == 0) - w3 O! G' X+ q* g: `. {% u: a
printf("buffer 2 equals buffer 1\n"); : i: v% U' ?( A) z- i) f
return 0;
# \5 x! O* X3 {' k} 5 ~/ n% }0 X V
4 P; q# }3 h9 ^& U+ [2 F, N7 A6 w

/ I- R1 y6 h' D( m7 j& O6 \8 c ?
- L3 s4 N/ |3 i* d- d2 d4 Y函数名: strcpy 
 a$ `; t+ Z2 \' D7 C1 ?0 X+ X功能: 串拷贝
% v; R0 D, F/ e D- Z8 J& x用法: char *strcpy(char *str1, char *str2);
3 `. g% H" g3 Y& ^: N! a程序例: 
8 @+ Z/ b1 e$ U#include <STDIO.H>- [/ ` p* ~5 v6 j' Z" I( C
#include <STRING.H>
& G \; A& w- u9 c+ Mint main(void)
) _9 H% s0 b& s: a{
+ {+ D; |; a& d2 t& j0 L& Z" l3 jchar string[10]; $ u0 j! ~4 E, M% u
char *str1 = "abcdefghi"; 
9 P( W+ O0 F6 Bstrcpy(string, str1); : \- v! K/ S0 U' F' A
printf("%s\n", string); - U9 w! {5 e0 a- ~; U2 g1 o
return 0;
6 @! O ^) f6 z- z" q. W! x Z} ! H! n9 m! o r5 _ W7 r q; y

, F6 [4 R1 W) V1 s6 J+ I4 ^8 e$ i) d1 ^& ?; p

7 V! H- b( H6 H; Y4 @" }" j% [6 h函数名: strcspn 
* F+ L8 S: h; L5 [3 ^& U功能: 在串中查找第一个给定字符集内容的段
' `( p3 X, _% T. _2 Q( O( V. i用法: int strcspn(char *str1, char *str2);
6 e6 V) M: q5 ], x6 N程序例: 
* i, H3 K0 u" K- C/ J a#include <STDIO.H>
# R# }: `. }8 b6 {! ^#include <STRING.H>
4 T S9 K2 P3 B# W#include <ALLOC.H>2 B/ h% \& O6 @8 A
int main(void) $ N# z1 a& y5 M/ L. h
{ ( `- e7 {5 P" {& L( r9 {- x
char *string1 = "1234567890";
8 v3 k0 w; Y" i5 _char *string2 = "747DC8"; 1 j, q* H# r. }; W
int length; * h' ?! w0 `3 L% n9 }2 d5 q
length = strcspn(string1, string2);
/ X; t$ Y) S' Mprintf("Character where strings intersect is at position %d\n", length); 
0 P# M4 P- |# O- ^' qreturn 0; 5 J5 n$ @) \# h: z
} 5 B, P1 g9 q8 L4 b4 w1 v
1 Z2 K1 r8 y% S: {: ^

" W6 M( S+ K1 n6 {- N4 h6 x
# I+ {. \ Z' l1 L函数名: strdup 
# r* U4 [( t+ x! v9 z" F. v" |功能: 将串拷贝到新建的位置处 : g$ g& C7 e3 K% q0 N" h$ G
用法: char *strdup(char *str);
/ {* C( P1 b k% Z3 D4 O1 ?0 W程序例: 5 }) O, x& h8 d" w2 X j1 [7 H4 t! x
#include <STDIO.H>
) Q3 s; \) @/ Y: b8 D#include <STRING.H>
" x$ ^+ b. ?8 d2 E, p8 G#include <ALLOC.H>
3 g/ d i" F5 k( o2 Iint main(void)
( w- w1 A* R- K{ 8 o8 r, _9 o \
char *dup_str, *string = "abcde"; 
- A* y, v! r' Z: ndup_str = strdup(string);
0 v; H' R8 \6 g z# i, ~2 kprintf("%s\n", dup_str);
: C+ [# h8 }1 j( G# `& x7 ?free(dup_str); % p) v2 P- u. q1 z/ S1 l# o1 M
return 0; - G7 k+ Y2 d% E/ _9 w
} . \0 ^/ }4 T" F- Q
: t. f9 k) j. F* s8 \7 K

2 Y* _5 F, x) x
 o( N8 T) b8 n8 o) W! Q函数名: stricmp " f' b7 k. b6 a: c$ Y4 V
功能: 以大小写不敏感方式比较两个串
 ~4 r5 d6 t7 \6 f6 b用法: int stricmp(char *str1, char *str2);
% k& X7 q( A; U; o! K程序例: 
! k9 n3 ~; _8 ?2 [3 P2 Q/ w _$ a#include <STRING.H>
8 o1 e$ G$ A4 Y$ w- N, B#include <STDIO.H>+ y5 s9 W: b* z& l/ f
int main(void)
- ?4 S9 t' Z/ q/ I{ : D% }, _5 U/ h) p
char *buf1 = "BBB", *buf2 = "bbb"; - E: h0 V- j a4 ~! `3 E: A s
int ptr; V% _) [( s$ \& I- x, i$ j
ptr = stricmp(buf2, buf1); / n" ^ H% D' n) m, R9 G) }; y' v
if (ptr > 0) 8 V: @: N# _3 j0 U8 J0 V5 _
printf("buffer 2 is greater than buffer 1\n"); 
0 B4 Z$ [% U9 U) t# {! X* vif (ptr < 0) - A) ?& @. ^+ ]/ [
printf("buffer 2 is less than buffer 1\n"); 4 l, q: \8 j1 a! ~: R
if (ptr == 0)
, j {: X$ R# O3 |printf("buffer 2 equals buffer 1\n"); a v7 i8 ^% E
return 0; $ U9 B' w/ a3 z/ f+ _( F% |
}
& T! _, f% c& ^1 w D/ d9 P: g: N3 o% Q1 X
5 V3 J: T8 f: z w) @/ N2 [- d! f
函数名: strerror 
$ E9 S2 W1 @7 B( c6 c" I& u功能: 返回指向错误信息字符串的指针 . m+ }( m; M! I' W" z" h$ E! Q
用法: char *strerror(int errnum);
; P* } B, A( N$ N0 ^& F程序例: : H6 I/ Q) V% q' }
#include <STDIO.H>
+ \3 C1 U0 d3 A) l#include <ERRNO.H>8 t! W2 R, ^6 m2 Z) ~. i
int main(void)
' G& J/ D" E$ z# m: y# a" ^{
$ J+ F1 W: T2 I; w6 U- Xchar *buffer;
$ g- H! o- ?6 ]0 G+ _- S) Cbuffer = strerror(errno);
) f" q* `, I, W0 a! ^printf("Error: %s\n", buffer);
. P0 m3 m' H1 }return 0; + k, h' S% X% c, v
}
. z/ ?, y, h. k& y' ~! a) z1 g4 @
. v% K2 P2 e3 K, n; u/ j

/ O+ U8 \, o# T# |( ~函数名: strcmpi % j2 K/ q; ?8 f7 M% ~
功能: 将一个串与另一个比较, 不管大小写 7 D* A$ @ G( k0 L! I3 _
用法: int strcmpi(char *str1, char *str2);
3 h4 a# P4 l8 S! d* U1 o9 Y程序例: 
' @; z5 Y7 n0 V#include <STRING.H>2 P) Y3 H0 O4 |. S
#include <STDIO.H>
% c( ?: O) P8 H+ ~9 k& kint main(void) - n( L1 W% T6 z4 }) c1 A; ]
{ * k5 q' E; u1 n) m! |
char *buf1 = "BBB", *buf2 = "bbb";
( b7 i! l1 ~" W: iint ptr; & u) H! L, ^0 q" C
ptr = strcmpi(buf2, buf1); 7 \6 {5 r* I$ o- m
if (ptr > 0) : D2 s0 j ]' q% k3 G7 \
printf("buffer 2 is greater than buffer 1\n"); ! r" t: C" f. H& [# P
if (ptr < 0) ! z/ q" l# S; i E
printf("buffer 2 is less than buffer 1\n"); - z1 m1 `3 N, b8 q ~. {
if (ptr == 0) ( D% J' {/ H/ U' g ]' F+ f
printf("buffer 2 equals buffer 1\n"); 
( F) r/ t) R9 i4 `5 @" xreturn 0;
( y o# P* E: { c, N}
3 g" b& ^( m+ ]
+ I' M$ w2 Z# q" \( A' }8 i
0 n( I$ d9 S2 C
0 \, Q- }7 s7 y$ Q9 L( J( e函数名: strncmp : l- w; G5 M0 f/ X6 R
功能: 串比较
7 W. z4 @! z B用法: int strncmp(char *str1, char *str2, int maxlen); C! ^4 T! x5 Q8 D& f5 u: F# y
程序例: 
6 e+ r: A. J) ?; y; Y2 [" s0 `2 Y#include <STRING.H>) J' @4 B; C( e- P( {
#include <STDIO.H>
+ w' w' d5 B. i3 wint main(void) 
5 ~; V1 P5 j7 z x' a( u, J( o{ f# w2 B' N. m+ g6 o
char *buf1 = "aaabbb", *buf2 = "bbbccc", *buf3 = "ccc";
9 B/ P. z- D' i5 cint ptr; . [$ X1 L& F, m+ l2 |
ptr = strncmp(buf2,buf1,3);
* o- c! i5 q% ~if (ptr > 0)
' j6 t f0 H/ \5 N9 [printf("buffer 2 is greater than buffer 1\n");
0 {' I% _( f2 _" v" d: Pelse ( v# Q& m' Q2 z( d8 B
printf("buffer 2 is less than buffer 1\n"); 
$ `1 v% A, ]3 U- z6 j' |4 wptr = strncmp(buf2,buf3,3); $ I a& G0 G# M
if (ptr > 0) 2 Y- h& j9 h J5 ~: z* v1 C/ Y
printf("buffer 2 is greater than buffer 3\n"); $ |3 y8 Q. G( I, _! D
else
, J( s+ Q% ^ x8 e; J( I8 vprintf("buffer 2 is less than buffer 3\n"); 6 z! ^/ L' r& h& o% G
return(0);
) }3 W! F. G, O+ o7 X! g} - C! M: ]& T/ p4 |
8 \) d6 a% w1 g! e! [

6 R) |! r7 u8 _$ ]* E$ ] S函数名: strncmpi + o$ L. H9 h _
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
) ~+ q3 x- |5 L. w; Y2 I4 X0 K# j用法: int strncmpi(char *str1, char *str2); 8 o5 l, [; k/ l
程序例: 1 Q+ U, ?7 a- E3 V3 c; {
#include <STRING.H>
" ]$ d8 A! c4 T2 W+ M#include <STDIO.H>4 ?4 J& N1 E( G
int main(void) / @( ^, N* {2 E6 ]% x( }
{ 7 W. w% l& o3 \4 s7 b/ w) ?
char *buf1 = "BBBccc", *buf2 = "bbbccc";
" q7 O4 g. w4 Z+ S7 ^* Cint ptr; 
( i8 [5 B9 P: X8 R! mptr = strncmpi(buf2,buf1,3); " O, _) X7 j5 F. J3 A5 @& p* N- P
if (ptr > 0) 5 }5 i5 N7 Q( H/ ^" X) N- m
printf("buffer 2 is greater than buffer 1\n"); 
* |0 f9 t; A ^' u% Sif (ptr < 0)
( [) j7 x( b3 o8 U% r! W/ _% Hprintf("buffer 2 is less than buffer 1\n"); 
; O! C. X$ C( ]( vif (ptr == 0) 4 V/ [% @( n1 ]/ U
printf("buffer 2 equals buffer 1\n"); ; E* ]" ^3 j) \' F* ~7 n: {5 K
return 0; 
- T& z- b! L! p& q' Y1 e8 e}
# F: o4 R* i9 x
) g) B4 o" g1 Z2 X; O; o& }; {
 h8 Q$ o) G& h8 a3 u$ u函数名: strncpy " }4 T+ ]9 N0 h" h: ?- p
功能: 串拷贝
. F8 `7 B9 i# Z( x- s用法: char *strncpy(char *destin, char *source, int maxlen);
0 d* J* M8 _7 Y* [0 e" w& j. c* a9 f程序例: 
! ]3 f2 m6 E" g& K8 [$ w0 n#include <STDIO.H>
, S/ f2 X) \$ r1 B" r- O#include <STRING.H>6 E5 P/ h1 f: V& q- k6 @
int main(void) + q0 T9 J5 R, W3 V1 k
{
( S$ k; R7 h, e( ?, j- A# M) cchar string[10];
- e( W) `' |) X- e8 T9 v( d zchar *str1 = "abcdefghi"; 6 l, o5 s6 `0 w0 O" n7 A6 P1 j3 D
strncpy(string, str1, 3); 7 L) Q7 t$ k, h; l8 V1 A. b
string[3] = '\0'; % a" t2 V2 l. T0 U) h
printf("%s\n", string); : e+ I+ U- \. T0 }. U% C. q& \- D1 J
return 0;
" i W$ z! w# ^' o# K* }} 2 D# V# e9 a- O
2 S h" m, E3 E' A! T: b
1 _+ B h8 P* H; l: M# V, {$ b
函数名: strnicmp 3 ~; {4 r4 B2 R9 q
功能: 不注重大小写地比较两个串 ) y3 R5 [, d6 ^4 J; o
用法: int strnicmp(char *str1, char *str2, unsigned maxlen);
; w; x. p2 T! W) k* K+ w3 N9 P程序例: 
7 e K, l0 c4 j% i9 b#include <STRING.H># E/ x d3 X8 n. u
#include <STDIO.H>
* m# l [2 }# d3 d/ J/ M% U- fint main(void)
* `: N; k" e3 U3 L9 [, {4 t; U0 _{ 0 N3 {; D2 D8 {& }& M8 K
char *buf1 = "BBBccc", *buf2 = "bbbccc";
( s' a H, _* J6 z# F! I# ~; E5 Sint ptr; 
% j$ s' X' o+ F6 @ptr = strnicmp(buf2, buf1, 3); - p/ V! F, q' |) H
if (ptr > 0)
# E r `! u- W/ x* [$ E4 ^+ {printf("buffer 2 is greater than buffer 1\n"); $ P5 Z- z/ e' A( S
if (ptr < 0) # X P. y$ f2 F1 h
printf("buffer 2 is less than buffer 1\n"); 
 ]7 K7 K+ s8 k5 l8 l* ]; @8 {if (ptr == 0) * _0 v# x8 a* f2 P: ~+ _8 @
printf("buffer 2 equals buffer 1\n"); 
 z/ X( e3 \4 W! lreturn 0; q% \) E7 C" t
}
, L" @2 q: Z, s \
7 |4 i" z& c8 J3 ~" W
+ k' Y7 t2 K5 y+ {5 F, q1 O* `$ F0 b
函数名: strnset 
/ e9 j, E% F/ R6 k0 L功能: 将一个串中的所有字符都设为指定字符 - }8 [1 o5 F) I& [8 Q6 V8 f
用法: char *strnset(char *str, char ch, unsigned n); " ]6 `7 P3 J* W: y. J( V
程序例: 
+ z( T- L- b( b( m#include <STDIO.H>
. ~& A9 r2 F( Q* a0 C" N: u$ o. d#include <STRING.H>* _! ?/ k t3 o8 Y
int main(void) & N7 |2 k/ i, y. D# s f$ Z/ c
{ 9 ]' x/ [( W9 j3 L' E7 B. O& \2 p
char *string = "abcdefghijklmnopqrstuvwxyz"; : D$ R! G9 |- z d4 K! A
char letter = 'x'; ! J) D9 R8 y; ~% Y, B' V
printf("string before strnset: %s\n", string); % w8 ?/ c R$ Z! D9 b6 o! f
strnset(string, letter, 13); " |2 Z: ]& S! E; t
printf("string after strnset: %s\n", string); 
3 {6 R% r6 D2 W2 x6 s9 B0 H- yreturn 0;
4 P T Q1 C7 v2 ]3 v# U}
* H, r' f( U+ o( k7 O/ Q! b
% j% a) d- D8 ~/ ?: h0 i5 I+ W- x E# P. e1 [
函数名: strpbrk / ~) E" x8 A$ }4 e: F8 W: O
功能: 在串中查找给定字符集中的字符 8 P& C2 u# \! u5 S' i& C
用法: char *strpbrk(char *str1, char *str2);
4 ]( X& F$ k" |" B T Q7 H程序例: ) m7 h7 M" f: m
#include <STDIO.H>- f4 S0 k! S$ s: J3 p$ _6 m! H
#include <STRING.H>/ ?; E" h1 Y; T9 K
int main(void)
* B+ j2 L: Y4 Y: V, N, Q{ 2 q+ T! o T# B/ b* \% Z0 J! w
char *string1 = "abcdefghijklmnopqrstuvwxyz"; ! E/ E2 u& h# n2 f# o
char *string2 = "onm"; 8 p7 Q' a1 M2 [8 m3 p8 ^7 Y
char *ptr; 
) R% k, u& [, q7 k i3 b0 I( Dptr = strpbrk(string1, string2); - G. N' b/ l; W. l( H8 h( U* ~
if (ptr)
3 A' x) B0 x1 q1 d* ]printf("strpbrk found first character: %c\n", *ptr); 1 \9 O$ O! v2 T2 b' P' b5 h
else
8 P% Q U$ Q/ F3 X/ J0 k# Cprintf("strpbrk didn't find character in set\n"); 
+ [* ]9 ^4 c a' \return 0;
4 `. w& d0 {3 N0 a} 0 k4 ] p0 P; Q2 L
6 f# ~5 N5 K4 F1 s& Z: J6 c, t

3 P# T, y9 d# D! V
) ^7 t1 ~( ^3 ~! I' T函数名: strrchr + G0 L, z& J% Y( L: b
功能: 在串中查找指定字符的最后一个出现
2 I3 }) V8 V3 ]# r3 L用法: char *strrchr(char *str, char c);
" Z) A' b) u; F1 C9 H- s% u程序例: 
 b5 c6 k% M' n$ [6 h#include <STRING.H>
( p( E O/ |' U#include <STDIO.H> W. R( w; p- `# |
int main(void) 6 W' [) l$ X. D5 S
{ 6 P6 N5 R3 f& X
char string[15];
 D9 W B+ P" ichar *ptr, c = 'r'; 8 }0 s, U- p! A2 a* l" L3 p+ P% `$ \
strcpy(string, "This is a string"); 9 w& A& U, r; V) s4 N) c ` S
ptr = strrchr(string, c); 6 d9 a$ U6 p! z
if (ptr) ' s# \8 f; ?' |
printf("The character %c is at position: %d\n", c, ptr-string);
# q; u6 }* i2 \else
+ k. N/ L) P: X% Q) Jprintf("The character was not found\n"); : l( G' ]5 a k0 P
return 0;
3 v# V1 n% j2 P1 l} 9 X" r, a/ n2 g$ i

/ F: k5 i: o7 x' {7 @4 `1 g
4 f1 V* t- d# G' U# ~; y
1 B3 Y( X( U! E2 k2 A6 L* b函数名: strrev " _# B& `5 V3 Y& v
功能: 串倒转
- m2 }+ T" u- C8 P8 j, ~/ z$ H5 _用法: char *strrev(char *str);
$ V, r7 Y6 M" s+ m程序例: 
( N* [7 f5 H* D, E7 ` Y' ^4 r#include <STRING.H>
6 J( x) \$ d6 o" l7 J- a- G J# @#include <STDIO.H>* d* T' Y# e: k; D* R F
int main(void) 6 N9 }: w$ p& m1 r7 g
{
! _) j! Z# e9 \1 j; N! H+ `$ {char *forward = "string"; 
. i- H5 u- m& X: `2 T/ @5 ], Uprintf("Before strrev(): %s\n", forward);
1 w x4 I, u3 z0 x# L3 }; _strrev(forward);
3 r! b r9 V# |# Nprintf("After strrev(): %s\n", forward);
: o$ K& f6 L" Z$ Q3 b3 jreturn 0;
: u2 \$ J* g2 H" ^% g} : F" P& w5 R3 s/ a2 a2 X
) O2 A: c( N1 C& z \3 w' u! @
函数名: strset 
2 ^+ m4 W5 b+ M3 w4 B( k4 u功能: 将一个串中的所有字符都设为指定字符 U' I: {: b$ B) K. T S; q" }
用法: char *strset(char *str, char c);
; R4 |/ N% ?0 I2 W3 C: K: _" P程序例: ( _/ X+ h1 W" f: f% M) x3 |
#include <STDIO.H>
. V& G2 G" D! v: B' `" l% s; h7 @4 W#include <STRING.H>
+ `' g7 t0 M" Lint main(void) " P4 _. y3 o1 \6 m7 T7 ]6 a
{ 7 ^: ~' }% `9 ^
char string[10] = "123456789"; 7 X3 n- F+ l6 R7 i$ f
char symbol = 'c'; 
4 ~9 @3 b* f$ u+ k7 P, s% w0 zprintf("Before strset(): %s\n", string);
" u& @' k" m* Y! ^. y1 ?& d7 \strset(string, symbol); ; v! O. z& l3 S1 e8 N# `, }- M
printf("After strset(): %s\n", string); ) v# @7 p, Y+ Z
return 0;
* k' x c, [( H N1 l}
' s9 ]+ F5 P1 U( p) ~
$ ?% {+ w$ v8 @% b" d. t5 J' n0 b3 h* i6 f2 B
8 I5 b$ z% O! I! Q% I2 A
函数名: strspn 4 a& P! i$ o7 E7 s/ N) N3 E
功能: 在串中查找指定字符集的子集的第一次出现 " _ Y. l: x( w& p+ W$ Z
用法: int strspn(char *str1, char *str2);
0 C7 E2 H% i" f2 W7 }程序例: 
+ P/ _) m! X% o" f#include <STDIO.H>
: T m' x3 I' \1 X+ _/ F#include <STRING.H>
) B/ Q- _* C- n& a6 R! [! L#include <ALLOC.H>
# Q2 Q- g4 ~- h2 w" L: Lint main(void) ; O& q \) e! s1 x( l
{
$ Y0 \/ ]' @% V$ k, I( j0 b" vchar *string1 = "1234567890";
) }: Y) x! Z8 m P( kchar *string2 = "123DC8";
6 q% H3 U7 Q& g! Fint length; 9 o1 L; b* I; T$ p0 m0 L" H
length = strspn(string1, string2);
, Z y4 x8 t wprintf("Character where strings differ is at position %d\n", length);
5 q f, s# x! p* R) w5 I, }return 0; ! B1 N6 ^7 K% p7 M Y
}
$ J' Q+ a8 F& l. [6 y( F
5 Q7 }, Z/ x" s" [ W4 n
2 ^6 u) p/ n& v: A函数名: strstr ( j3 X' Q/ {, i% h* u. ]7 A
功能: 在串中查找指定字符串的第一次出现
: ?; o& d0 j! n用法: char *strstr(char *str1, char *str2); * w; ?3 ^ F# l& o- Q
程序例: 0 @- s$ A7 e* N
#include <STDIO.H>
9 X; O6 N h& Z! a#include <STRING.H>
9 s- v9 u/ @& p- [$ ^4 dint main(void) 7 T# U2 l# C& X/ I9 R
{
4 g1 q i1 f5 p6 q0 p6 b" D4 l# dchar *str1 = "Borland International", *str2 = "nation", *ptr; 
( h! B- M' w J5 y7 @$ X0 nptr = strstr(str1, str2);
$ W, ^% p) g7 M/ @3 W2 l; ~printf("The substring is: %s\n", ptr);
. M" m. e- v0 V7 ureturn 0;
 G' W. R3 p6 e7 g/ }$ Y! P} , [" }1 T" o- L3 u% X+ W6 D* m a/ I2 ~
6 ` a" s( {8 Z- l6 C% F' e3 t0 {
$ a+ W; a3 R9 w, F* b. q: f
函数名: strtod 
7 I( x- \6 [0 I+ K7 H& X功能: 将字符串转换为double型值
, P- y7 C( |: L用法: double strtod(char *str, char **endptr); * ]+ l7 B/ X6 A9 a0 e9 s) p
程序例: ! u$ n, z" n6 h& r* E
#include <STDIO.H>8 L+ p9 q3 i$ B2 g4 A( U
#include <STDLIB.H># `+ U# P; t% X9 z& k. P+ Y/ x
int main(void) ( e6 h( ]: g; s& c C8 M
{
4 m8 j4 a( p8 x0 h" ~1 Pchar input[80], *endptr; 0 Y( n2 _# ]. }! }2 m
double value; 
7 K- `% M% s( P) Bprintf("Enter a floating point number:");
+ ^. \: r e+ sgets(input); & [2 {( @9 q/ i% J2 \5 F& x
value = strtod(input, &endptr); 9 X; l0 z6 e2 G1 F Q7 K3 W5 t% F- @8 B
printf("The string is %s the number is %lf\n", input, value); ) }8 n' N; J# n7 H
return 0; - A% h3 h+ F! c+ s+ S
} 3 B4 e0 ~9 t: F$ g, }4 i1 j4 V- X) Q
, O% ]& R( z# L7 |! Y" ~' J

, |7 l8 I. C9 }2 `& ~) `8 o; n5 V
/ e" c' a# \6 ~函数名: strtok / F: y2 q/ Y* p
功能: 查找由在第二个串中指定的分界符分隔开的单词
# G' y9 C6 H: j1 a! p用法: char *strtok(char *str1, char *str2);
 ?" u8 w# Z1 _" w# b程序例: 
0 ~( i+ X' `5 q+ A3 c#include <STRING.H>' W) b i+ [) a3 T! y( K" O6 ]
#include <STDIO.H>
/ Y) G( q8 @( aint main(void) ( I; E# d6 H, ~& |) _
{
; p9 U5 `# G! E& ?. f' q7 [char input[16] = "abc,d"; & u8 x. O# ?! }& q. N6 {
char *p; J0 S0 s$ h6 N- w5 q# P; h& ^
/* strtok places a NULL terminator . c; I5 Y$ V" _; V- z
in front of the token, if found */
) Y9 i* H5 H! M' O4 ap = strtok(input, ","); % N- h; F( L1 f0 y9 D1 l$ i
if (p) printf("%s\n", p); 
. k$ H1 s, U3 [: u* k# l0 ^/* A second call to strtok using a NULL # |8 U$ i# l- s# c' o
as the first parameter returns a pointer
/ ]4 C+ t9 e9 k/ S8 oto the character following the token */
- @$ ^0 Z( |4 P5 ]1 c* J! J rp = strtok(NULL, ","); $ b' B1 j$ o! L g1 ?) i* X
if (p) printf("%s\n", p); % U( t- S# p9 |) N$ b0 x
return 0;
' N' A7 f: |# x* Z7 Q/ E; Y} + L; u& \! w$ c) Z
4 F T# `& s' u% B+ B/ Y) \. a8 ?

+ [, I+ {, Q9 i5 Q2 @3 x$ r
7 d: \4 g3 h* v0 _( a/ e函数名: strtol ; Z, X0 h4 S. r( B8 j3 P: Z+ `/ W
功能: 将串转换为长整数
. o: V) e6 {' |用法: long strtol(char *str, char **endptr, int base); 4 }2 Z- p% m6 _4 r; C6 C- q
程序例: 
7 C$ m) Z& t" h& y#include <STDLIB.H>
' h) \9 @; f3 L D% B( _- c#include <STDIO.H>
/ y& T) h" S& X0 d5 Wint main(void)
) z; c) ~: u T& q9 N8 d{ $ ^+ H" m, ? H! L
char *string = "87654321", *endptr;
" w3 O7 l: R" E+ [: z4 Xlong lnumber; + r# _. b0 W8 R# s
/* strtol converts string to long integer */ - p' f9 h% I' M5 A# o
lnumber = strtol(string, &endptr, 10); 5 @. @- _, L& }+ j* K
printf("string = %s long = %ld\n", string, lnumber); 
# p5 j$ i( F8 _0 D. C2 Treturn 0;
' g3 I- l _9 U0 P: ~} 
% A2 r% j @8 F" F
3 A( X, i, j# }函数名: strupr ) |0 \- J# ]- r/ o8 T
功能: 将串中的小写字母转换为大写字母
2 F2 n/ W g) Y# M# f; N用法: char *strupr(char *str); 7 ^9 L' H7 u- t" f
程序例: 6 J! j6 f7 `% m& ?0 c4 D: M0 d1 `3 \
#include <STDIO.H>
/ C! \& M x, Y3 Z. f#include <STRING.H>- e% S1 \0 k% z7 t) A* ]
int main(void)
8 K$ i6 [7 ]8 D{ ) M. N( a D9 u% G
char *string = "abcdefghijklmnopqrstuvwxyz", *ptr; 
( ?. D! m* T! }/* converts string to upper case characters */ + z9 V& F5 X4 E. G. o: s) U6 x
ptr = strupr(string);
* K! l) {) h# k# R) c5 Bprintf("%s\n", ptr); , D& I: F* o6 C
return 0; / w9 }0 f7 v: }4 i0 w% a% I
} & w) j$ B3 B4 a, L4 j
" F2 l" b0 M6 }3 Y, J& g: H
0 w& a, k% p3 L$ a4 N. ^) [

 {* ~* n# `* c函数名: swab 
8 i% l, ]7 E; m1 f功能: 交换字节 * R) b6 s" n8 F/ ]) }
用法: void swab (char *from, char *to, int nbytes); 2 E( w" `/ z) y% p3 Q% t- L
程序例: 
4 J' v8 m* u- E; g: f, u#include <STDLIB.H>6 \! o ^0 g, f9 V0 F+ z
#include <STDIO.H>
! \; j# r! |3 _* D! Y#include <STRING.H>9 O4 F0 L9 W, `+ `: p1 f; m
char source[15] = "rFna koBlrna d"; , S$ r+ Y1 v, U* Z; A1 _
char target[15]; 
+ a {, R" X& L: iint main(void)
/ k- x& x8 } _* v{ 9 w) _2 r, t" L; b4 C
swab(source, target, strlen(source));
4 q7 @8 ?/ l0 q: B" k2 p: x. dprintf("This is target: %s\n", target);
% u+ n D8 [! J, x$ Q6 W* areturn 0; & @% ~( O8 j4 ?
} 3 i, w. }$ G7 S. D( Z' c3 k8 G7 @$ ]' G
9 o# c- `: r) W

/ K* I4 v; L# A! X! J* W& r- `/ l+ p+ ` D
函数名: system 0 I0 l/ _- F4 F7 B
功能: 发出一个DOS命令 / L/ @7 h! d+ ~6 Q& w+ m" a: y d
用法: int system(char *command);
6 ]0 o `* Z. V程序例: 7 t% j0 M$ d4 F* v' a+ T5 d' ~
#include <STDLIB.H>
# T3 l: |- Z; Q$ ~5 X6 A#include <STDIO.H>% d+ z) M: V$ P& T" y3 r5 a
int main(void)
; b$ M+ }5 P/ U0 R- M{ ; T* L% q* [6 l- S" N5 o: a0 \! d W5 i
printf("About to spawn command.com and run a DOS command\n");
$ \( F r; h' c; s h. Isystem("dir");
; c; j' A. I1 G: d/ Creturn 0;
5 h( k/ _! |. t2 ]& A1 n} 

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