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Diffstat (limited to 'man3/putenv.3')
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diff --git a/man3/putenv.3 b/man3/putenv.3 deleted file mode 100644 index c63d5e4..0000000 --- a/man3/putenv.3 +++ /dev/null @@ -1,141 +0,0 @@ -'\" t -.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" References consulted: -.\" Linux libc source code -.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) -.\" 386BSD man pages -.\" Single UNIX Specification, Version 2 -.\" Modified Thu Apr 8 15:00:12 1993, David Metcalfe -.\" Modified Sat Jul 24 18:44:45 1993, Rik Faith (faith@cs.unc.edu) -.\" Modified Fri Feb 14 21:47:50 1997 by Andries Brouwer (aeb@cwi.nl) -.\" Modified Mon Oct 11 11:11:11 1999 by Andries Brouwer (aeb@cwi.nl) -.\" Modified Wed Nov 10 00:02:26 1999 by Andries Brouwer (aeb@cwi.nl) -.\" Modified Sun May 20 22:17:20 2001 by Andries Brouwer (aeb@cwi.nl) -.TH putenv 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -putenv \- change or add an environment variable -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <stdlib.h> -.P -.BI "int putenv(char *" string ); -.\" Not: const char * -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR putenv (): -.nf - _XOPEN_SOURCE - || /* glibc >= 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _SVID_SOURCE -.fi -.SH DESCRIPTION -The -.BR putenv () -function adds or changes the value of environment -variables. -The argument \fIstring\fP is of the form \fIname\fP=\fIvalue\fP. -If \fIname\fP does not already exist in the environment, then -\fIstring\fP is added to the environment. -If \fIname\fP does exist, -then the value of \fIname\fP in the environment is changed to -\fIvalue\fP. -The string pointed to by \fIstring\fP becomes part of the environment, -so altering the string changes the environment. -.SH RETURN VALUE -The -.BR putenv () -function returns zero on success. -On failure, it returns a nonzero value, and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B ENOMEM -Insufficient space to allocate new environment. -.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 putenv () -T} Thread safety MT-Unsafe const:env -.TE -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, SVr2, 4.3BSD-Reno. -.P -The -.BR putenv () -function is not required to be reentrant, and the -one in glibc 2.0 is not, but the glibc 2.1 version is. -.\" .P -.\" Description for libc4, libc5, glibc: -.\" If the argument \fIstring\fP is of the form \fIname\fP, -.\" and does not contain an \[aq]=\[aq] character, then the variable \fIname\fP -.\" is removed from the environment. -.\" If -.\" .BR putenv () -.\" has to allocate a new array \fIenviron\fP, -.\" and the previous array was also allocated by -.\" .BR putenv (), -.\" then it will be freed. -.\" In no case will the old storage associated -.\" to the environment variable itself be freed. -.P -Since glibc 2.1.2, the glibc implementation conforms to SUSv2: -the pointer \fIstring\fP given to -.BR putenv () -is used. -In particular, this string becomes part of the environment; -changing it later will change the environment. -(Thus, it is an error to call -.BR putenv () -with an automatic variable -as the argument, then return from the calling function while \fIstring\fP -is still part of the environment.) -However, from glibc 2.0 to glibc 2.1.1, it differs: -a copy of the string is used. -On the one hand this causes a memory leak, and on the other hand -it violates SUSv2. -.P -The 4.3BSD-Reno version, like glibc 2.0, uses a copy; -this is fixed in all modern BSDs. -.P -SUSv2 removes the \fIconst\fP from the prototype, and so does glibc 2.1.3. -.P -The GNU C library implementation provides a nonstandard extension. -If -.I string -does not include an equal sign: -.P -.in +4n -.EX -putenv("NAME"); -.EE -.in -.P -then the named variable is removed from the caller's environment. -.SH SEE ALSO -.BR clearenv (3), -.BR getenv (3), -.BR setenv (3), -.BR unsetenv (3), -.BR environ (7) |