.\" Copyright 2001 John Levon <moz@compsoc.man.ac.uk>
.\"
+.\" %%%LICENSE_START(VERBATIM)
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
+.\" %%%LICENSE_END
.\"
.\" Additions, aeb, 2001-10-17.
-.TH CLEARENV 3 2007-07-26 "Linux" "Linux Programmer's Manual"
+.TH CLEARENV 3 2010-10-04 "Linux" "Linux Programmer's Manual"
.SH NAME
clearenv \- clear the environment
.SH SYNOPSIS
.in
.sp
.BR clearenv ():
-_SVID_SOURCE || _XOPEN_SOURCE
+_SVID_SOURCE || _BSD_SOURCE
.SH DESCRIPTION
The
.BR clearenv ()
pairs and sets the value of the external variable
.I environ
to NULL.
-.SH "RETURN VALUE"
+.SH RETURN VALUE
The
.BR clearenv ()
-function returns zero on success, and a non-zero
+function returns zero on success, and a nonzero
value on failure.
-.\" Most versions of Unix return -1 on error, or do not even have errors.
-.\" Glibc info and the Watcom C library document "a non-zero value".
+.\" Most versions of UNIX return -1 on error, or do not even have errors.
+.\" Glibc info and the Watcom C library document "a nonzero value".
.SH VERSIONS
Not in libc4, libc5.
In glibc since glibc 2.0.
-.SH "CONFORMING TO"
-Various Unix variants (DG/UX, HP-UX, QNX, ...).
+.SH CONFORMING TO
+Various UNIX variants (DG/UX, HP-UX, QNX, ...).
POSIX.9 (bindings for FORTRAN77).
POSIX.1-1996 did not accept
.BR clearenv ()
will return an error and the process environment will remain unchanged.
.\" .LP
.\" HP-UX has a ENOMEM error return.
-.SH "SEE ALSO"
+.SH SEE ALSO
.BR getenv (3),
.BR putenv (3),
.BR setenv (3),