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Turbo C 2.0、Borland C++库函数及用例(26) }
函数名: ferror
功 能: 检测流上的错误
用 法: int ferror(FILE *stream);
程序例:#include <stdio.h>int main(void)
{
FILE *stream; /* open a file for writing */
stream = fopen("DUMMY.FIL", "w");
/* force an error condition by attempting to read */
(void) getc(stream); if (ferror(stream)) /*test for an error on the stream*/
{
/* display an error message */
printf("Error reading from DUMMY.FIL\n"); /* reset the error and EOF indicators */
clearerr(stream);
} fclose(stream);
return 0;
}
函数名: fflush
功 能: 清除一个流
用 法: int fflush(FILE *stream);
程序例:#include <string.h>
#include <stdio.h>
#include <conio.h>
#include <io.h>void flush(FILE *stream);int main(void)
{ FILE *stream;
char msg[] = "This is a test"; /* create a file */
stream = fopen("DUMMY.FIL", "w"); /* write some data to the file */
fwrite(msg, strlen(msg), 1, stream); clrscr();
printf("Press any key to flush\
DUMMY.FIL:");
getch(); /* flush the data to DUMMY.FIL without\
closing it */
flush(stream); printf("\nFile was flushed, Press any key\
to quit:");
getch();
return 0;
}void flush(FILE *stream)
{
int duphandle; /* flush the stream's internal buffer */
fflush(stream); /* make a duplicate file handle */
duphandle = dup(fileno(stream)); /* close the duplicate handle to flush\
the DOS buffer */
close(duphandle);
}
函数名: fgetc
功 能: 从流中读取字符
用 法: int fgetc(FILE *stream);
程序例:#include <string.h>
#include <stdio.h>
#include <conio.h>int main(void)
{
FILE *stream;
char string[] = "This is a test";
char ch; /* open a file for update */
stream = fopen("DUMMY.FIL", "w+");
/* write a string into the file */
fwrite(string, strlen(string), 1, stream);
/* seek to the beginning of the file */
fseek(stream, 0, SEEK_SET);
do
{
/* read a char from the file */
ch = fgetc(stream); /* display the character */
putch(ch);
} while (ch != EOF); fclose(stream);
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