2 .\" Copyright (c) 1992, X/Open Company Limited. All Rights Reserved. Portions Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved.
3 .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
4 .\" http://www.opengroup.org/bookstore/.
5 .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
6 .\" This notice shall appear on any product containing this material.
7 .\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
8 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
9 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
10 .TH FFLUSH 3C "Nov 1, 2003"
12 fflush \- flush a stream
18 \fBint\fR \fBfflush\fR(\fBFILE *\fR\fIstream\fR);
24 If \fIstream\fR points to an output stream or an update stream in which the
25 most recent operation was not input, \fBfflush()\fR causes any unwritten data
26 for that stream to be written to the file, and the \fBst_ctime\fR and
27 \fBst_mtime\fR fields of the underlying file are marked for update.
30 If \fIstream\fR points to an input stream or an update stream into which the
31 most recent operation was input, that stream is flushed if it is seekable and
32 is not already at end-of-file. Flushing an input stream discards any buffered
33 input and adjusts the file pointer such that the next input operation accesses
34 the byte after the last one read. A stream is seekable if the underlying file
35 is not a pipe, FIFO, socket, or TTY device.
38 If \fIstream\fR is a null pointer, \fBfflush()\fR performs this flushing action
39 on all streams for which the behavior is defined above.
42 An input stream, seekable or non-seekable, can be flushed by explicitly calling
43 \fBfflush()\fR with a non-null argument specifying that stream.
47 Upon successful completion, \fBfflush()\fR returns \fB0\fR. Otherwise, it
48 returns \fBEOF\fR and sets \fBerrno\fR to indicate the error.
52 The \fBfflush()\fR function will fail if:
59 The \fBO_NONBLOCK\fR flag is set for the file descriptor underlying
60 \fIstream\fR and the process would be delayed in the write operation.
69 The file descriptor underlying \fIstream\fR is not valid.
78 An attempt was made to write a file that exceeds the maximum file size or the
79 process's file size limit; or the file is a regular file and an attempt was
80 made to write at or beyond the offset maximum associated with the corresponding
90 The \fBfflush()\fR function was interrupted by a signal.
99 The process is a member of a background process group attempting to write to
100 its controlling terminal, \fBTOSTOP\fR is set, the process is neither ignoring
101 nor blocking \fBSIGTTOU\fR, and the process group of the process is orphaned.
110 There was no free space remaining on the device containing the file.
119 An attempt is made to write to a pipe or \fBFIFO\fR that is not open for
120 reading by any process. A \fBSIGPIPE\fR signal will also be sent to the calling
126 The \fBfflush()\fR function may fail if:
133 A request was made of a non-existent device, or the request was beyond the
134 limits of the device.
140 See \fBattributes\fR(5) for descriptions of the following attributes:
148 ATTRIBUTE TYPE ATTRIBUTE VALUE
150 Interface Stability Standard
158 \fBgetrlimit\fR(2), \fBulimit\fR(2), \fBattributes\fR(5), \fBstandards\fR(5)