4.3 dprintf, vdprintf—print to a file descriptor

Synopsis

#include <stdio.h>
#include <stdarg.h>
int dprintf(int fd, const char *restrict format, ...);
int vdprintf(int fd, const char *restrict format,
    va_list ap);
int _dprintf_r(struct _reent *ptr, int fd,
    const char *restrict format, ...);
int _vdprintf_r(struct _reent *ptr, int fd,
    const char *restrict format, va_list ap);

Description
dprintf and vdprintf allow printing a format, similarly to printf, but write to a file descriptor instead of to a FILE stream.

The functions _dprintf_r and _vdprintf_r are simply reentrant versions of the functions above.

Returns
The return value and errors are exactly as for write, except that errno may also be set to ENOMEM if the heap is exhausted.

Portability
This function is originally a GNU extension in glibc and is not portable.

Supporting OS subroutines required: sbrk, write.