g.txt

C语言库函数介绍

srand(seed); 
for (i=0; i<PIXEL_COUNT; i++) 
{ 
x = random(maxx); 
y = random(maxy); 
color = random(maxcolor); 
putpixel(x, y, color); 
} 
delay(DELAY_TIME); 
srand(seed); 
for (i=0; i<PIXEL_COUNT; i++) 
{ 
x = random(maxx); 
y = random(maxy); 
color = random(maxcolor); 
if (color ==名: gets 
功 能: 从流中取一字符串 
用 法: char *gets(char *string); 
程序例: 

#include <stdio.h> 

int main(void) 
{ 
char string[80]; 

printf("Input a string:"); 
gets(string); 
printf("The string input was: %s\n", 
string); 
return 0; 
} 
函数名: gettext 
功 能: 将文本方式屏幕上的文本拷贝到存储区 
用 法: int gettext(int left, int top, int right, int bottom, void *destin); 
程序例: 
#include <conio.h> 
char buffer[4096]; 
int main(void) 
{ int i; 
clrscr(); 
for (i = 0; i <= 20; i++) 
cprintf("Line #%d\r\n", i); 
gettext(1, 1, 80, 25, buffer); 
gotoxy(1, 25); 
cprintf("Press any key to clear screen..."); 
getch(); 
clrscr(); 
gotoxy(1, 25); 
cprintf("Press any key to restore screen..."); 
getch(); 
puttext(1, 1, 80, 25, buffer); 
gotoxy(1, 25); 
cprintf("Press any key to quit..."); 
getch(); 
return 0; 
} 
函数名: gettextinfo 
功 能: 取得文本模式的显示信息 
用 法: void gettextinfo(struct text_info *inforec); 
程序例: 
#include <conio.h> 

int main(void) 
{ 
struct text_info ti; 
gettextinfo(&ti); 
cprintf("window left %2d\r\n",ti.winleft); 
cprintf("window top %2d\r\n",ti.wintop); 
cprintf("window right %2d\r\n",ti.winright); 
cprintf("window bottom %2d\r\n",ti.winbottom); 
cprintf("attribute %2d\r\n",ti.attribute); 
cprintf("normal attribute %2d\r\n",ti.normattr); 
cprintf("current mode %2d\r\n",ti.currmode); 
cprintf("screen height %2d\r\n",ti.screenheight); 
cprintf("screen width %2d\r\n",ti.screenwidth); 
cprintf("current x %2d\r\n",ti.curx); 
cprintf("current y %2d\r\n",ti.cury); 
return 0; 
} 
函数名: gettextsettings 
功 能: 返回有关当前图形文本字体的信息 
用 法: void far gettextsettings(struct textsettingstype far *textinfo); 
程序例: 
#include <graphics.h> 
#include <stdlib.h> 
#include <stdio.h> 
#include <conio.h> 
/* the names of the fonts supported */ 
char *font[] = { "DEFAULT_FONT", 
"TRIPLEX_FONT", 
"SMALL_FONT", 
"SANS_SERIF_FONT", 
"GOTHIC_FONT" 
}; 
/* the names of the text directions supported */ 
char *dir[] = { "HORIZ_DIR", "VERT_DIR" }; 
/* horizontal text justifications supported */ 
char *hjust[] = { "LEFT_TEXT", "CENTER_TEXT", "RIGHT_TEXT" }; 
/* vertical text justifications supported */ 
char *vjust[] = { "BOTTOM_TEXT", "CENTER_TEXT", "TOP_TEXT" }; 
int main(void) 
{ /* request auto detection */ 
int gdriver = DETECT, gmode, errorcode; 
struct textsettingstype textinfo; 
int midx, midy, ht; 
char fontstr[80], dirstr[80], sizestr[80]; 
char hjuststr[80], vjuststr[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 */ 
} 
midx = getmaxx() / 2; 
midy = getmaxy() / 2; 
/* get information about current text settings */ 
gettextsettings(&textinfo); 
/* convert text information into strings */ 
sprintf(fontstr, "%s is the text style.", font[textinfo.font]); 
sprintf(dirstr, "%s is the text direction.", dir[textinfo.direction]); 
sprintf(sizestr, "%d is the text size.", textinfo.charsize); 
sprintf(hjuststr, "%s is the horizontal justification.", 
hjust[textinfo.horiz]); 
sprintf(vjuststr, "%s is the vertical justification.", 
vjust[textinfo.vert]); 
/* display the information */ 
ht = textheight("W"); 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
outtextxy(midx, midy, fontstr); 
outtextxy(midx, midy+2*ht, dirstr); 
outtextxy(midx, midy+4*ht, sizestr); 
outtextxy(midx, midy+6*ht, hjuststr); 
outtextxy(midx, midy+8*ht, vjuststr); 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: gettime 
功 能: 取得系统时间 
用 法: void gettime(struct time *timep); 
程序例: 

#include <stdio.h> 
#include <dos.h> 

int main(void) 
{ struct time t; 
gettime(&t); 
printf("The current time is: %2d:%02d:%02d.%02d\n", 
t.ti_hour, t.ti_min, t.ti_sec, t.ti_hund); 
return 0; 
} 
函数名: getvect 
功 能: 取得中断向量入口 
用 法: void interrupt(*getvect(int intr_num)); 
程序例: 
#include <stdio.h> 
#include <dos.h> 
void interrupt get_out(); /* interrupt prototype */ 
void interrupt (*oldfunc)(); /* interrupt function pointer */ 
int looping = 1; 
int main(void) 
{ 
puts("Press <Shift><Prt Sc> to terminate"); 
/* save the old interrupt */ 
oldfunc = getvect(5); 
/* install interrupt handler */ 
setvect(5,get_out); 
/* do nothing */ 
while (looping); 
/* restore to original interrupt routine */ 
setvect(5,oldfunc); 
puts("Success"); 
return 0; 
} void interrupt get_out() 
{ 
looping = 0; /* change global variable to get out of loop */ 
} 
函数名: getverify 
功 能: 返回DOS校验标志状态 
用 法: int getverify(void); 
程序例: 
#include <stdio.h> 
#include <dos.h> 
int main(void) 
{ if (getverify()) 
printf("DOS verify flag is on\n"); 
else 
printf("DOS verify flag is off\n"); 
return 0; 
} 
函数名: getviewsetting 
功 能: 返回有关当前视区的信息 
用 法: void far getviewsettings(struct viewporttype far *viewport); 
程序例: 
#include <graphics.h> 
#include <stdlib.h> 
#include <stdio.h> 
#include <conio.h> 
char *clip[] = { "OFF", "ON" }; 
int main(void) 
{ /* request auto detection */ 
int gdriver = DETECT, gmode, errorcode; 
struct viewporttype viewinfo; 
int midx, midy, ht; 
char topstr[80], botstr[80], clipstr[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 */ 
} midx = getmaxx() / 2; 
midy = getmaxy() / 2; 
/* get information about current viewport */ 
getviewsettings(&viewinfo); 
/* convert text information into strings */ 
sprintf(topstr, "(%d, %d) is the upper left viewport corner.", 
viewinfo.left, viewinfo.top); 
sprintf(botstr, "(%d, %d) is the lower right viewport corner.", 
viewinfo.right, viewinfo.bottom); 
sprintf(clipstr, "Clipping is turned %s.", clip[viewinfo.clip]); 
/* display the information */ 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
ht = textheight("W"); 
outtextxy(midx, midy, topstr); 
outtextxy(midx, midy+2*ht, botstr); 
outtextxy(midx, midy+4*ht, clipstr); 

/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getw 
功 能: 从流中取一整数 
用 法: int getw(FILE *strem); 
程序例: 
#include <stdio.h> 
#include <stdlib.h> 
#define FNAME "test.$$$" 
int main(void) 
{ 
FILE *fp; 
int word; 
/* place the word in a file */ 
fp = fopen(FNAME, "wb"); 
if (fp == NULL) 
{ 
printf("Error opening file %s\n", FNAME); 
exit(1); 
} 
word = 94; 
putw(word,fp); 
if (ferror(fp)) 
printf("Error writing to file\n"); 
else 
printf("Successful write\n"); 
fclose(fp); 
/* reopen the file */ 
fp = fopen(FNAME, "rb"); 
if (fp == NULL) 
{ 
printf("Error opening file %s\n", FNAME); 
exit(1); 
} 
/* extract the word */ 
word = getw(fp); 
if (ferror(fp)) 
printf("Error reading file\n"); 
else 
printf("Successful read: word = %d\n", word); 

/* clean up */ 
fclose(fp); 
unlink(FNAME); 
return 0; 
} 
函数名: getx 
功 能: 返回当前图形位置的x坐标 
用 法: int far getx(void); 
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; 
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 */ 
} 
/* move to the screen center point */ 
moveto(getmaxx() / 2, getmaxy() / 2); 
/* create a message string */ 
sprintf(msg, "<-(%d, %d) is the here.", getx(), gety()); 
/* display the message */ 
outtext(msg); 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getdate 
功 能: 取DOS日期 
用 法: void getdate(struct *dateblk); 
程序例: 
#include <dos.h> 
#include <stdio.h> 
int main(void) 
{ struct date d; 
getdate(&d); 
 printf("The current year is: %d\n", 
d.da_year); 
printf("The current day is: %d\n", 
d.da_day); 
printf("The current month is: %d\n", d.da_mon); return 0; 
} 
函数名: getdefaultpalette 
功 能: 返回调色板定义结构 
用 法: struct palettetype *far getdefaultpalette(void); 
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 i; 
/* structure for returning palette copy */ 
struct palettetype far *pal=(void *) 0; 
/* initialize graphics and local variables */ 
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */ 
errorcode = graphresult(); 
/* an error occurred */ 
if (errorcode != grOk) 
{ 
printf("Graphics error: %s\n", 
grapherrormsg(errorcode)); 
printf("Press any key to halt:"); 
getch(); 
/* terminate with an error code */ 
exit(1); 
} 
setcolor(getmaxcolor()); 
/* return a pointer to the default palette */ 
pal = getdefaultpalette(); 

for (i=0; i<16; i++) 
{ printf("colors[%d] = %d\n", i, 
pal->colors[i]); 
getch(); 
} 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getdisk 
功 能: 取当前磁盘驱动器号 
用 法: int getdisk(void); 
程序例: 
#include <stdio.h> 
#include <dir.h> 
int main(void) 
{ int disk; 
disk = getdisk() + 'A'; 
printf("The current drive is: %c\n", 
disk); 
return 0; 
} 
函数名: getdrivername 
功 能: 返回指向包含当前图形驱动程序名字的字符串指针 
用 法: char *getdrivename(void); 
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; 
/* stores the device driver name */ 
char *drivername; 
/* initialize graphics and local variables */ 
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */ 
errorcode = graphresult(); 
/* an error occurred */ 
if (errorcode != grOk) 
{ 
printf("Graphics error: %s\n", 
grapherrormsg(errorcode)); 
printf("Press any key to halt:"); 
getch(); 
/* terminate with an error code */ 
exit(1); 
} 
setcolor(getmaxcolor()); 

/* ge