C语言函数大全(s开头) (1)

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
#include

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
#include

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
{
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
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
#include

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
#include
#include
#include

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("Press 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
{
/ 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
#include

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
#include
#include
#include

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, "");

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
#include
#include
#include

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, "");

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
#include
#include
#include

int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int xasp, yasp, midx, midy;

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

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
#include
#include
#include

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, "");

/* 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
#include
#include
#include

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

/* 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
#include
#include

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
#include
#include
#include

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, "");

/* 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
#include
#include

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
#include

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
#include
#include
#include

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
#include
#include
#include

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, "");

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
#include
#include
#include
#include

/* 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, "");

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
#include
#include
#include

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
#include
#include
#include

#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, "");

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
#include
#include #include

int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int x, y;

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

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
#include
#include

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
#include
#include
#include
#include

/* 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, "");

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
#include
#include

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
#include
#include

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
#include
#include
#include

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, "");

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
#include
#include
#include

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, "");

/* grab a copy of the palette */
getpalette(&pal);

/* create gray scale /
for (i=0; i
setrgbpalette(pal.colors[i], i4, i4, i4);

/* display the gray scale */
ht = getmaxy() / 16;
xmax = getmaxx();
y = 0;
for (i=0; i
{
setfillstyle(SOLID_FILL, i);
bar(0, y, xmax, y+ht);
y += ht;
}

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

函数名: settextjustify
功能: 为图形函数设置文本的对齐方式
用法: void far settextjustify(int horiz, int vert);
程序例:

#include
#include
#include
#include

/* function prototype */
void xat(int x, int y);

/* horizontal text justification settings */
char *hjust[] = { "LEFT_TEXT",
"CENTER_TEXT",
"RIGHT_TEXT"
};

/* vertical text justification settings */
char *vjust[] = { "LEFT_TEXT",
"CENTER_TEXT",
"RIGHT_TEXT"
};

int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int midx, midy, hj, vj;
char msg[80];

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

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

/* loop through text justifications /
for (hj=LEFT_TEXT; hj<=RIGHT_TEXT; hj++)
for (vj=LEFT_TEXT; vj<=RIGHT_TEXT; vj++)
{
cleardevice();
/ set the text justification */
settextjustify(hj, vj);

/* create a message string */
sprintf(msg, "%s %s", hjust[hj], vjust[vj]);

/* create cross hairs on the screen */
xat(midx, midy);

/* output the message */
outtextxy(midx, midy, msg);
getch();
}

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

/* draw an "x" at (x, y) */
void xat(int x, int y)
{
line(x-4, y, x+4, y);
line(x, y-4, x, y+4);
}

函数名: settextstyle
功能: 为图形输出设置当前的文本属性
用法: void far settextstyle (int font, int direction, char size);
程序例:

#include
#include
#include
#include

/* the names of the text styles supported */
char *fname[] = { "DEFAULT font",
"TRIPLEX font",
"SMALL font",
"SANS SERIF font",
"GOTHIC font"
};

int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int style, midx, midy;
int size = 1;

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

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

settextjustify(CENTER_TEXT, CENTER_TEXT);

/* loop through the available text styles */
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++)
{
cleardevice();
if (style == TRIPLEX_FONT)
size = 4;

/* select the text style */
settextstyle(style, HORIZ_DIR, size);

/* output a message */
outtextxy(midx, midy, fname[style]);
getch();
}

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

函数名: settextstyle
功能: 为图形输出设置当前的文本属性
用法: void far settextstyle (int font, int direction, char size);
程序例:

#include
#include
#include
#include

/* the names of the text styles supported */
char *fname[] = { "DEFAULT font",
"TRIPLEX font",
"SMALL font",
"SANS SERIF font",
"GOTHIC font"
};

int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;
int style, midx, midy;
int size = 1;

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

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

settextjustify(CENTER_TEXT, CENTER_TEXT);

/* loop through the available text styles */
for (style=DEFAULT_FONT; style<=GOTHIC_FONT; style++)
{
cleardevice();
if (style == TRIPLEX_FONT)
size = 4;

/* select the text style */
settextstyle(style, HORIZ_DIR, size);

/* output a message */
outtextxy(midx, midy, fname[style]);
getch();
}

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

函数名: settime
功能: 设置系统时间
用法: void settime(struct time *timep);
程序例:

#include
#include

int main(void)
{
struct time t;

gettime(&t);
printf("The current minute is: %d\n", t.ti_min);
printf("The current hour is: %d\n", t.ti_hour);
printf("The current hundredth of a second is: %d\n", t.ti_hund);
printf("The current second is: %d\n", t.ti_sec);

/* Add one to the minutes struct element and then call settime */
t.ti_min++;
settime(&t);

return 0;
}

函数名: setusercharsize
功能: 为矢量字体改变字符宽度和高度
用法: void far setusercharsize(int multx, int dirx, int multy, int diry);
程序例:

#include
#include
#include
#include

int main(void)
{
/* request autodetection */
int gdriver = DETECT, gmode, errorcode;

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

/* select a text style */
settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4);

/* move to the text starting position */
moveto(0, getmaxy() / 2);

/* output some normal text */
outtext("Norm ");

/* make the text 1/3 the normal width */
setusercharsize(1, 3, 1, 1);
outtext("Short ");

/* make the text 3 times normal width */
setusercharsize(3, 1, 1, 1);
outtext("Wide");

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

函数名: setvbuf
功能: 把缓冲区与流相关
用法: int setvbuf(FILE *stream, char *buf, int type, unsigned size);
程序例:

#include

int main(void)
{
FILE *input, *output;
char bufr[512];

input = fopen("file.in", "r+b");
output = fopen("file.out", "w");

/* set up input stream for minimal disk access,
using our own character buffer */
if (setvbuf(input, bufr, _IOFBF, 512) != 0)
printf("failed to set up buffer for input file\n");
else
printf("buffer set up for input file\n");

/* set up output stream for line buffering using space that
will be obtained through an indirect call to malloc */
if (setvbuf(output, NULL, _IOLBF, 132) != 0)
printf("failed to set up buffer for output file\n");
else
printf("buffer set up for output file\n");

/* perform file I/O here */

/* close files */
fclose(input);
fclose(output);
return 0;
}

函数名: setvect
功能: 设置中断矢量入口
用法: void setvect(int intr_num, void interrupt(*isr)());
程序例:

/***NOTE:
This is an interrupt service routine. You can NOT compile this
program with Test Stack Overflow turned on and get an executable
file which will operate correctly. */

#include
#include
#include

#define INTR 0X1C /* The clock tick interrupt */

void interrupt ( *oldhandler)(void);

int count=0;

void interrupt handler(void)
{
/* increase the global counter */
count++;

/* call the old routine */
oldhandler();
}

int main(void)
{
/* save the old interrupt vector */
oldhandler = getvect(INTR);

/* install the new interrupt handler */
setvect(INTR, handler);

/* loop until the counter exceeds 20 */
while (count < 20)
printf("count is %d\n",count);

/* reset the old interrupt handler */
setvect(INTR, oldhandler);

return 0;
}

函数名: setverify
功能: 设置验证状态
用法: void setverify(int value);
程序例:

#include
#include
#include

int main(void)
{
int verify_flag;

printf("Enter 0 to set verify flag off\n");
printf("Enter 1 to set verify flag on\n");

verify_flag = getch() - 0;

setverify(verify_flag);

if (getverify())
printf("DOS verify flag is on\n");
else
printf("DOS verify flag is off\n");

return 0;
}

函数名: setviewport
功能: 为图形输出设置当前视口
用法: void far setviewport(int left, int top, int right,
int bottom, int clipflag);
程序例:

#include
#include
#include
#include

#define CLIP_ON 1 /* activates clipping in viewport */

int main(void)
{
/* request auto detection */
int gdriver = DETECT, gmode, errorcode;

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

setcolor(getmaxcolor());

/* message in default full-screen viewport /
outtextxy(0, 0, " <-- (0, 0) in default viewport");

/* create a smaller viewport */
setviewport(50, 50, getmaxx()-50, getmaxy()-50, CLIP_ON);

/* display some text /
outtextxy(0, 0, " <-- (0, 0) in smaller viewport");

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