Name

fread, fwrite − buffered binary input/output

Syntax

#include <stdio.h>

 size_t fread(ptr, size, nitems, stream)
void *ptr;
size_t size, nitems;
FILE *stream;
 size_t fwrite(ptr, size, nitems, stream)
void *ptr;
size_t size, nitems;
FILE *stream;

Description

The fread function reads into a block beginning at ptr, nitems of data of the size size (usually sizeof *ptr) from the named input stream. It returns the number of items actually read.

If stream is stdin and the standard output is line buffered, then any partial output line will be flushed before any call to read() to satisfy the fread.

The fwrite function appends, at most, nitems of data of the size size (usually sizeof *ptr) beginning at ptr to the named output stream. It returns the number of items actually written.

Return Values

The fread and fwrite functions return 0 upon end of file or error.

See Also

read(2), write(2), fopen(3s), getc(3s), gets(3s), printf(3s), putc(3s), puts(3s), scanf(3s)