CLEARENV(3)

NAME
clearenv - clear the environment

SYNOPSIS
#include <stdlib.h>

int clearenv(void);

DESCRIPTION
The clearenv() function clears the environment of all name-value pairs.

RETURN VALUE
The clearenv() function returns zero on success, and a non-zero value on failure.

AVAILABILITY
Not in libc4, libc5. In glibc since glibc 2.0.

CONFORMING TO
Various Unix variants (DGUX, HPUX, QNX, ...). POSIX.9 (bindings for FORTRAN77). POSIX.1-1996 did not accept clearenv() and putenv(), but changed its mind and scheduled these functions for some later issue of this standard (cf. B.4.6.1). However, SUSv3 only adds putenv(), and rejected clearenv().

NOTES
Used in security-conscious applications. If it is unavailable the assignment
    	environ = NULL;
will probably do.

SEE ALSO
getenv(3), putenv(3), setenv(3), unsetenv(3), environ(5)