03-11-2010
While I would mostly agree with the file descriptor definition, a file pointer is not usually what you describe but commonly used to refer to what the standard C library uses to handle files (FILE *).
The associated functions are fopen, fclose, fread, fwrite, fscanf and the likes.
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LEARN ABOUT ULTRIX
fwrite
fread(3s) fread(3s)
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 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 to satisfy the
The 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 and 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)
fread(3s)