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 analogues of fprintf() and vfprintf(), except that they out- put to a file descriptor fd instead of to a given stream.

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 dprintf(), usually some debugging version of printf(), perhaps with a prototype like

void dprintf (int level, const char *format, ...);

where the first parameter is a debugging level (and output is to stderr). Moreover, dprintf() (or DPRINTF) is also a popular macro name for a debugging printf. So, probably, it is better to avoid this func- tion in programs intended to be portable.

A better name would have been fdprintf().

CONFORMING TO These functions are GNU extensions.

SEE ALSO printf(3)

GNU 2001-12-18 DPRINTF(3)