'\" te .\" Copyright (c) 2001, the Institute of Electrical and Electronics Engineers, Inc. and The Open Group. All Rights Reserved. .\" Portions Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved. .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at http://www.opengroup.org/bookstore/. .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html. This notice shall appear on any product containing this material. .TH setenv 3C "31 Mar 2002" "SunOS 5.11" "Standard C Library Functions" .SH NAME setenv \- add or change environment variable .SH SYNOPSIS .LP .nf #include \fBint\fR \fBsetenv\fR(\fBconst char *\fR\fIenvname\fR, \fBconst char *\fR\fIenvval\fR, \fBint\fR \fIoverwrite\fR); .fi .SH DESCRIPTION .sp .LP The \fBsetenv()\fR function updates or adds a variable in the environment of the calling process. The \fIenvname\fR argument points to a string containing the name of an environment variable to be added or altered. The environment variable is set to the value to which \fIenvval\fR points. The function fails if \fIenvname\fR points to a string which contains an '=' character. If the environment variable named by \fIenvname\fR already exists and the value of \fIoverwrite\fR is non-zero, the function returns successfully and the environment is updated. If the environment variable named by \fIenvname\fR already exists and the value of \fIoverwrite\fR is zero, the function returns successfully and the environment remains unchanged. .sp .LP If the application modifies \fIenviron\fR or the pointers to which it points, the behavior of \fBsetenv()\fR is undefined. The \fBsetenv()\fR function updates the list of pointers to which \fIenviron\fR points. .sp .LP The strings described by \fIenvname\fR and \fIenvval\fR are copied by this function. .SH RETURN VALUES .sp .LP Upon successful completion, 0 is returned. Otherwise, -1 is returned, \fBerrno\fR set to indicate the error, and the environment is left unchanged. .SH ERRORS .sp .LP The \fBsetenv()\fR function will fail if: .sp .ne 2 .mk .na \fB\fBEINVAL\fR\fR .ad .RS 10n .rt The \fIenvname\fR argument is a null pointer, points to an empty string, or points to a string containing an '=' character. .RE .sp .ne 2 .mk .na \fB\fBENOMEM\fR\fR .ad .RS 10n .rt Insufficient memory was available to add a variable or its value to the environment. .RE .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-LevelMT-Safe _ StandardSee \fBstandards\fR(5). .TE .SH SEE ALSO .sp .LP \fBgetenv\fR(3C), \fBunsetenv\fR(3C), \fBattributes\fR(5), \fBstandards\fR(5)