4.27 __fsetlocking—set or query locking mode on FILE stream

Synopsis

#include <stdio.h>
#include <stdio_ext.h>
int __fsetlocking(FILE *fp, int type);

Description
This function sets how the stdio functions handle locking of FILE fp. The following values describe type:

FSETLOCKING_INTERNAL is the default state, where stdio functions automatically lock and unlock the stream.

FSETLOCKING_BYCALLER means that automatic locking in stdio functions is disabled. Applications which set this take all responsibility for file locking themselves.

FSETLOCKING_QUERY returns the current locking mode without changing it.

Returns
__fsetlocking returns the current locking mode of fp.

Portability
This function originates from Solaris and is also provided by GNU libc.

No supporting OS subroutines are required.