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Turbo C 2.0、Borland C++库函数及用例(13) {
int handle;
char buf[11] = "0123456789"; /* create a file containing 10 bytes */
handle = open("NEW.FIL", O_CREAT);
if (handle > -1)
{
write(handle, buf, strlen(buf)); /* close the file */
close(handle);
}
else
{
printf("Error opening file\n");
} return 0;
}
函数名: clock
功 能: 确定处理器时间
用 法: clock_t clock(void);
程序例:#include <time.h>
#include <stdio.h>
#include <dos.h>int main(void)
{
clock_t start, end;
start = clock();
delay(2000); end = clock();
printf("The time was: %f\n", (end - start) / CLK_TCK); return 0;
}
函数名: closegraph
功 能: 关闭图形系统
用 法: void far closegraph(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 x, y; /* initialize graphics mode */
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 a key to close the graphics \
system:"); /* wait for a key */
getch();
/* closes down the graphics system */
closegraph(); printf("We're now back in text mode.\n");
printf("Press any key to halt:");
getch();
return 0;
}
函数名: clreol
功 能: 在文本窗口中清除字符到行末
用 法: void clreol(void);
程序例:#include <conio.h>int main(void)
{
clrscr();
cprintf("The function CLREOL clears all characters from\
the\r\n");
cprintf("cursor position to the end of the line within\
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