summaryrefslogtreecommitdiffstats
path: root/man3/clearenv.3
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-24 04:52:22 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-24 04:52:22 +0000
commit3d08cd331c1adcf0d917392f7e527b3f00511748 (patch)
tree312f0d1e1632f48862f044b8bb87e602dcffb5f9 /man3/clearenv.3
parentAdding debian version 6.7-2. (diff)
downloadmanpages-3d08cd331c1adcf0d917392f7e527b3f00511748.tar.xz
manpages-3d08cd331c1adcf0d917392f7e527b3f00511748.zip
Merging upstream version 6.8.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'man3/clearenv.3')
-rw-r--r--man3/clearenv.3137
1 files changed, 0 insertions, 137 deletions
diff --git a/man3/clearenv.3 b/man3/clearenv.3
deleted file mode 100644
index 3ffd761..0000000
--- a/man3/clearenv.3
+++ /dev/null
@@ -1,137 +0,0 @@
-'\" t
-.\" Copyright 2001 John Levon <moz@compsoc.man.ac.uk>
-.\"
-.\" SPDX-License-Identifier: Linux-man-pages-copyleft
-.\"
-.\" Additions, aeb, 2001-10-17.
-.TH clearenv 3 2023-10-31 "Linux man-pages 6.7"
-.SH NAME
-clearenv \- clear the environment
-.SH LIBRARY
-Standard C library
-.RI ( libc ", " \-lc )
-.SH SYNOPSIS
-.nf
-.B #include <stdlib.h>
-.P
-.B "int clearenv(void);"
-.fi
-.P
-.RS -4
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.RE
-.P
-.BR clearenv ():
-.nf
- /* glibc >= 2.19: */ _DEFAULT_SOURCE
- || /* glibc <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE
-.fi
-.SH DESCRIPTION
-The
-.BR clearenv ()
-function clears the environment of all name-value
-pairs and sets the value of the external variable
-.I environ
-to NULL.
-After this call, new variables can be added to the environment using
-.BR putenv (3)
-and
-.BR setenv (3).
-.SH RETURN VALUE
-The
-.BR clearenv ()
-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 nonzero value".
-.SH ATTRIBUTES
-For an explanation of the terms used in this section, see
-.BR attributes (7).
-.TS
-allbox;
-lbx lb lb
-l l l.
-Interface Attribute Value
-T{
-.na
-.nh
-.BR clearenv ()
-T} Thread safety MT-Unsafe const:env
-.TE
-.SH STANDARDS
-.TP
-.BR putenv ()
-POSIX.1-2008.
-.TP
-.BR clearenv ()
-None.
-.SH HISTORY
-.TP
-.BR putenv ()
-glibc 2.0.
-POSIX.1-2001.
-.TP
-.BR clearenv ()
-glibc 2.0.
-.P
-Various UNIX variants (DG/UX, HP-UX, QNX, ...).
-POSIX.9 (bindings for FORTRAN77).
-POSIX.1-1996 did not accept
-.BR clearenv ()
-and
-.BR putenv (3),
-but changed its mind and scheduled these functions for some
-later issue of this standard (see \[sc]B.4.6.1).
-However, POSIX.1-2001
-adds only
-.BR putenv (3),
-and rejected
-.BR clearenv ().
-.SH NOTES
-On systems where
-.BR clearenv ()
-is unavailable, the assignment
-.P
-.in +4n
-.EX
-environ = NULL;
-.EE
-.in
-.P
-will probably do.
-.P
-The
-.BR clearenv ()
-function may be useful in security-conscious applications that want to
-precisely control the environment that is passed to programs
-executed using
-.BR exec (3).
-The application would do this by first clearing the environment
-and then adding select environment variables.
-.P
-Note that the main effect of
-.BR clearenv ()
-is to adjust the value of the pointer
-.BR environ (7);
-this function does not erase the contents of the buffers
-containing the environment definitions.
-.P
-The DG/UX and Tru64 man pages write: If
-.I environ
-has been modified by anything other than the
-.BR putenv (3),
-.BR getenv (3),
-or
-.BR clearenv ()
-functions, then
-.BR clearenv ()
-will return an error and the process environment will remain unchanged.
-.\" .P
-.\" HP-UX has a ENOMEM error return.
-.SH SEE ALSO
-.BR getenv (3),
-.BR putenv (3),
-.BR setenv (3),
-.BR unsetenv (3),
-.BR environ (7)