__fbufsize, __flbf, __fpending, __fpurge, __freadable, __freading, __fsetlocking, __fwritable, __fwriting, _flushlbf — interfaces to stdio FILE structure
#include <stdio.h> #include <stdio_ext.h>
size_t __fbufsize( |
FILE *stream); |
size_t __fpending( |
FILE *stream); |
int __flbf( |
FILE *stream); |
int __freadable( |
FILE *stream); |
int __fwritable( |
FILE *stream); |
int __freading( |
FILE *stream); |
int __fwriting( |
FILE *stream); |
int __fsetlocking( |
FILE *stream, |
int type); |
void _flushlbf( |
void); |
void __fpurge( |
FILE *stream); |
Solaris introduced routines to allow portable access to the internals of the FILE structure, and glibc also implemented these.
The __fbufsize() function
returns the size of the buffer currently used by the given
stream.
The __fpending() function
returns the number of bytes in the output buffer. For
wide-oriented streams the unit is wide characters. This
function is undefined on buffers in reading mode, or opened
read-only.
The __flbf() function
returns a nonzero value if the stream is line-buffered, and
zero otherwise.
The __freadable() function
returns a nonzero value if the stream allows reading, and
zero otherwise.
The __fwritable() function
returns a nonzero value if the stream allows writing, and
zero otherwise.
The __freading() function
returns a nonzero value if the stream is read-only, or if the
last operation on the stream was a read operation, and zero
otherwise.
The __fwriting() function
returns a nonzero value if the stream is write-only (or
append-only), or if the last operation on the stream was a
write operation, and zero otherwise.
The __fsetlocking() function
can be used to select the desired type of locking on the
stream. It returns the current type. The type argument can take the
following three values:
FSETLOCKING_INTERNALPerform implicit locking around every operation on the given stream (except for the *_unlocked ones). This is the default.
FSETLOCKING_BYCALLERThe caller will take care of the locking (possibly
using flockfile(3) in case
there is more than one thread), and the stdio routines
will not do locking until the state is reset to
FSETLOCKING_INTERNAL.
FSETLOCKING_QUERYDon't change the type of locking. (Only return it.)
The _flushlbf() function
flushes all line-buffered streams. (Presumably so that output
to a terminal is forced out, say before reading keyboard
input.)
The __fpurge() function
discards the contents of the stream's buffer.
This page is part of release 3.24 of the Linux man-pages project. A
description of the project, and information about reporting
bugs, can be found at
http://www.kernel.org/doc/man-pages/.
|
Copyright (C) 2001 Andries Brouwer <aebcwi.nl>. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. |