'\" te
.\" Copyright (c) 2007, Sun Microsystems Inc. All Rights Reserved.
.\" Portions of this manual page are derived from documentation obtained from linuxmanpages.com
.TH dirfd 3C "24 Oct 2007" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
dirfd \- get directory stream file descriptor
.SH SYNOPSIS
.LP
.nf
#include <dirent.h>

\fBint\fR \fBdirfd\fR(\fBDIR *\fR\fIdir\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBdirfd()\fR function returns the file descriptor associated with the directory stream \fIdir\fR.
.sp
.LP
This file descriptor is the one used internally by the directory stream operations. See \fBopendir\fR(3C), \fBclosedir\fR(3C), \fBreaddir\fR(3C), \fBrewinddir\fR(3C), \fBseekdir\fR(3C), \fBtelldir\fR(3C).  The file descriptor is automatically closed when \fBclosedir()\fR is called for the directory stream \fIdir\fR or when one of the \fBexec\fR functions is called.  See \fBexec\fR(2).
.sp
.LP
The file descriptor can safely be used only by functions that do not depend on or alter the file position, such as \fBfstat\fR(2) and \fBfchdir\fR(2).  Closing the file descriptor with \fBclose\fR(2) or modifying the file position by means other than the directory stream operations listed above causes undefined behavior to occur when one of the directory stream operations is subsequently called with the directory stream \fIdir\fR.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, the \fBdirfd()\fR function returns an open file descriptor for the directory associated with the directory stream \fIdir\fR.
.SH ERRORS
.sp
.LP
There are no defined error returns.  Passing an invalid directory stream as an argument to the \fBdirfd()\fR function results in undefined behavior.
.SH USAGE
.sp
.LP
The \fBdirfd()\fR function is intended to be used to obtain a file descriptor for use with the \fBfchdir()\fR function.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
MT-LevelSafe
.TE

.SH SEE ALSO
.sp
.LP
\fBclose\fR(2), \fBexec\fR(2), \fBfchdir\fR(2), \fBfstat\fR(2), \fBclosedir\fR(3C), \fBopendir\fR(3C), \fBreaddir\fR(3C), \fBrewinddir\fR(3C), \fBseekdir\fR(3C), \fBtelldir\fR(3C), \fBattributes\fR(5)