.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>
.\" Text fragments inspired by Martin Schulze <joey@infodrom.org>.
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.TH DPRINTF 3 2010-09-15 "GNU" "Linux Programmer's Manual"
.SH NAME
dprintf, vdprintf \- print to a file descriptor
.SH SYNOPSIS
.B #include <stdio.h>
.sp
.BI "int dprintf(int " fd ", const char *" format ", ...);"
.sp
.BI "int vdprintf(int " fd ", const char *" format ", va_list " ap );
.sp
.in -4n
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.in
.sp
.BR dprintf (),
.BR vdprintf ():
.PD 0
.ad l
.RS 4
.TP 4
Since glibc 2.10:
_XOPEN_SOURCE\ >=\ 700 || _POSIX_C_SOURCE\ >=\ 200809L
.TP
Before glibc 2.10:
_GNU_SOURCE
.RE
.ad
.PD
.SH DESCRIPTION
The functions
.BR dprintf ()
and
.BR vdprintf ()
(as found in the glibc2 library) are exact analogs of
.BR fprintf (3)
and
.BR vfprintf (3),
except that they output to a file descriptor
.I fd
instead of to a
.I stdio
stream.
.SH CONFORMING TO
These functions are GNU extensions that are nowadays specified in
POSIX.1-2008.
.\" .SH NOTES
.\" These functions are GNU extensions, not in C or POSIX.
.\" Clearly, the names were badly chosen.
.\" Many systems (like MacOS) have incompatible functions called
.\" .BR dprintf (),
.\" usually some debugging version of
.\" .BR printf (3),
.\" perhaps with a prototype like
.\"
.\" .BI "void dprintf(int level, const char *" format ", ...);"
.\"
.\" where the first argument is a debugging level (and output is to
.\" .IR stderr ).
.\" Moreover,
.\" .BR dprintf ()
.\" (or
.\" .BR DPRINTF )
.\" is also a popular macro name for a debugging printf.
.\" So, probably, it is better to avoid this function in programs
.\" intended to be portable.
.\"
.\" A better name would have been
.\" .BR fdprintf ().
.SH SEE ALSO
.BR printf (3)
.SH COLOPHON
This page is part of release 3.74 of the Linux
.I man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
\%http://www.kernel.org/doc/man\-pages/.