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fwrite(3s) [bsd man page]

FREAD(3S)																 FREAD(3S)

NAME
fread, fwrite - buffered binary input/output SYNOPSIS
#include <stdio.h> fread(ptr, sizeof(*ptr), nitems, stream) FILE *stream; fwrite(ptr, sizeof(*ptr), nitems, stream) FILE *stream; DESCRIPTION
Fread reads, into a block beginning at ptr, nitems of data of the type of *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(2) to satisfy the fread. Fwrite appends at most nitems of data of the type of *ptr beginning at ptr to the named output stream. It returns the number of items actually written. SEE ALSO
read(2), write(2), fopen(3S), getc(3S), putc(3S), gets(3S), puts(3S), printf(3S), scanf(3S) DIAGNOSTICS
Fread and fwrite return 0 upon end of file or error. 4th Berkeley Distribution May 15, 1985 FREAD(3S)

Check Out this Related Man Page

FREAD(3)						   BSD Library Functions Manual 						  FREAD(3)

NAME
fread, fwrite -- binary stream input/output LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <stdio.h> size_t fread(void *restrict ptr, size_t size, size_t nitems, FILE *restrict stream); size_t fwrite(const void *restrict ptr, size_t size, size_t nitems, FILE *restrict stream); DESCRIPTION
The function fread() reads nitems objects, each size bytes long, from the stream pointed to by stream, storing them at the location given by ptr. The function fwrite() writes nitems objects, each size bytes long, to the stream pointed to by stream, obtaining them from the location given by ptr. RETURN VALUES
The functions fread() and fwrite() advance the file position indicator for the stream by the number of bytes read or written. They return the number of objects read or written. If an error occurs, or the end-of-file is reached, the return value is a short object count (or zero). The function fread() does not distinguish between end-of-file and error; callers must use feof(3) and ferror(3) to determine which occurred. The function fwrite() returns a value less than nitems only if a write error has occurred. SEE ALSO
read(2), write(2) STANDARDS
The functions fread() and fwrite() conform to ISO/IEC 9899:1990 (``ISO C90''). BSD
March 8, 1994 BSD
Man Page

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