SETENV(3) Linux Programmer's Manual SETENV(3)
NAME
setenv - change or add an environment variable
SYNOPSIS
#include<stdlib.h>
intsetenv(constchar*name,constchar*value,int overwrite);
voidunsetenv(constchar*name);
DESCRIPTION
The setenv() function adds the variable name to the environment with
the value value, if name does not already exist. If name does exist in
the environment, then its value is changed to value if overwrite is
non-zero; if overwrite is zero, then the value of name is not changed.
The unsetenv() function deletes the variable name from the environment.
RETURNVALUE
The setenv() function returns zero on success, or -1 if there was
insufficient space in the environment.
CONFORMINGTO
BSD 4.3
SEEALSO
clearenv(3), getenv(3), putenv(3), environ(5)
BSD 1993-04-04 SETENV(3)
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