$ man dprintf
DPRINTF(3) Linux Programmer’s Manual DPRINTF(3)
NAME
dprintf, vdprintf - print to a file descriptor
SYNOPSIS
#define _GNU_SOURCE
#include <stdio.h>
int dprintf(int fd, const char *format, ...);
int vdprintf(int fd, const char *format, va_list ap);
DESCRIPTION
The functions dprintf() and vdprintf() (as found in the glibc2 library)
are exact analogs of fprintf(3) and vfprintf(3),
except that they output to a file descriptor fd instead of to a stdio stream.
CONFORMING TO
These functions are GNU extensions that are nowadays specified in POSIX.1-2008
SEE ALSO
printf(3), feature_test_macros(7)
COLOPHON
This page is part of release 3.22 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/.
GNU 2008-08-06 DPRINTF(3)
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