fileno(3)fileno(3)NAMEfileno - Map a stream pointer to a file descriptor
SYNOPSIS
#include <stdio.h>
int fileno(
FILE *stream );
LIBRARY
Standard C Library (libc)
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
fileno(): XSH5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
PARAMETERS
Specifies the input stream.
DESCRIPTION
The fileno() function returns the integer file descriptor associated
with the stream pointed to by stream.
NOTES
[Tru64 UNIX] The fileno() function may be a macro (depending on the
compile-time definitions used in the source). Consequently, you cannot
use this interface where a function is necessary; for example, a sub‐
routine pointer cannot point to the interface.
RETURN VALUES
Upon successful completion, the fileno() macro returns the integer
value of the file descriptor associated with the stream parameter. Oth‐
erwise, the value -1 is returned.
SEE ALSO
Functions: open(2), clearerr(3), fdopen(3), feof(3), ferror(3),
fopen(3)
Standards: standards(5)fileno(3)