setenv.c File Reference

#include "c.h"

Include dependency graph for setenv.c:

Go to the source code of this file.

Functions
int	setenv (const char *name, const char *value, int overwrite)

Function Documentation

setenv()

int setenv	(	const char *	name,
		const char *	value,
		int	overwrite
	)

Definition at line 20 of file setenv.c.

References malloc, putenv, and sprintf.

{
    char       *envstr;

    /* Error conditions, per POSIX */
    if (name == NULL || name[0] == '\0' || strchr(name, '=') != NULL ||
        value == NULL)
    {
        errno = EINVAL;
        return -1;
    }

    /* No work if variable exists and we're not to replace it */
    if (overwrite == 0 && getenv(name) != NULL)
        return 0;

    /*
     * Add or replace the value using putenv().  This will leak memory if the
     * same variable is repeatedly redefined, but there's little we can do
     * about that when sitting atop putenv().
     */
    envstr = (char *) malloc(strlen(name) + strlen(value) + 2);
    if (!envstr)                /* not much we can do if no memory */
        return -1;

    sprintf(envstr, "%s=%s", name, value);

    return putenv(envstr);
}