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.TH FEXECVE 3 2010-09-15 "Linux" "Linux Programmer's Manual"
.SH NAME
fexecve \- execute program specified via file descriptor
.SH SYNOPSIS
.nf
.B #include <unistd.h>
.sp
.BI "int fexecve(int " fd ", char *const " argv "[], char *const " envp []);
.fi
.sp
.in -4n
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.in
.sp
.BR fexecve ():
.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
.BR fexecve ()
performs the same task as
.BR execve (2),
with the difference that the file to be executed
is specified via a file descriptor,
.IR fd ,
rather than via a pathname.
The file descriptor
.I fd
must be opened read-only,
and the caller must have permission to execute the file that it refers to.
.\" POSIX.1-2008 specifies the O_EXEC flag for open as an alternative,
.\" but Linux doesn't support this flag yet.
.SH "RETURN VALUE"
A successful call to
.BR fexecve ()
never returns.
On error, the function returns, with a result value of \-1, and
.I errno
is set appropriately.
.SH ERRORS
Errors are as for
.BR execve (2),
with the following additions:
.TP
.B EINVAL
.I fd
is not a valid file descriptor, or
.I argv
is NULL, or
.I envp
is NULL.
.TP
.B ENOSYS
The
.I /proc
file system could not be accessed.
.SH VERSIONS
.BR fexecve ()
is implemented since glibc 2.3.2.
.SH "CONFORMING TO"
POSIX.1-2008.
This function is not specified in POSIX.1-2001,
and is not widely available on other systems.
.SH NOTES
On Linux,
.BR fexecve ()
is implemented using the
.BR proc (5)
file system, so
.I /proc
needs to be mounted and available at the time of the call.
.SH "SEE ALSO"
.BR execve (2)
.SH COLOPHON
This page is part of release 3.44 of the Linux
.I man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.