C语言函数大全(p开头)

文章作者 100test 发表时间 2007:03:10 17:25:50
来源 100Test.Com百考试题网

函数名: parsfnm
功 能: 分析文件名
用 法: char *parsfnm (char *cmdline, struct fcb *fcbptr, int option).
程序例:
#include
#include
#include
#include
int main(void)
{
char line[80].
struct fcb blk.
/* get file name */
printf("Enter drive and file name (no path - ie. a:file.dat)\n").
gets(line).
/* put file name in fcb */
if (parsfnm(line, &.blk, 1) == NULL)
printf("Error in parsfm call\n").
else
printf("Drive #%d Name: s\n", blk.fcb_drive, blk.fcb_name).
return 0.
}


函数名: peek
功 能: 检查存储单元
用 法: int peek(int segment, unsigned offset).
程序例:
#include
#include
#include
int main(void)
{
int value = 0.
printf("The current status of your keyboard is:\n").
value = peek(0x0040, 0x0017).
if (value &. 1)
printf("Right shift on\n").
else
printf("Right shift off\n").
if (value &. 2)
printf("Left shift on\n").
else
printf("Left shift off\n").
if (value &. 4)
printf("Control key on\n").
else
printf("Control key off\n").
if (value &. 8)
printf("Alt key on\n").
else
printf("Alt key off\n").
if (value &. 16)
printf("Scroll lock on\n").
else
printf("Scroll lock off\n").
if (value &. 32)
printf("Num lock on\n").
else
printf("Num lock off\n").
if (value &. 64)
printf("Caps lock on\n").
else
printf("Caps lock off\n").
return 0.
}


函数名: peekb
功 能: 检查存储单元
用 法: char peekb (int segment, unsigned offset).
程序例:
#include
#include
#include
int main(void)
{
int value = 0.
printf("The current status of your keyboard is:\n").
value = peekb(0x0040, 0x0017).
if (value &. 1)
printf("Right shift on\n").
else
printf("Right shift off\n").
if (value &. 2)
printf("Left shift on\n").
else
printf("Left shift off\n").
if (value &. 4)
printf("Control key on\n").
else
printf("Control key off\n").
if (value &. 8)
printf("Alt key on\n").
else
printf("Alt key off\n").
if (value &. 16)
printf("Scroll lock on\n").
else
printf("Scroll lock off\n").
if (value &. 32)
printf("Num lock on\n").
else
printf("Num lock off\n").
if (value &. 64)
printf("Caps lock on\n").
else
printf("Caps lock off\n").
return 0.
}


函数名: perror
功 能: 系统错误信息
用 法: void perror(char *string).
程序例:
#include
int main(void)
{
FILE *fp.
fp = fopen("perror.dat", "r").
if (!fp)
perror("Unable to open file for reading").
return 0.