explain_unsetenv_or_die - remove an environment variable and report errors

       libexplain version 1.4
       Copyright (C) 2010 Peter Miller

                                                                                      explain_unsetenv_or_die(3)

       The  explain_unsetenv_or_die  function  is  used  to  call  the  unsetenv(3)  system  call. On failure an
       explanation will be printed to stderr, obtained from  the  explain_unsetenv(3)  function,  and  then  the
       process terminates by calling exit(EXIT_FAILURE).

       The  explain_unsetenv_on_error  function  is  used  to  call  the  unsetenv(3) system call. On failure an
       explanation will be printed to stderr, obtained from the explain_unsetenv(3) function, but still  returns
       to the caller.

       name    The name, exactly as to be passed to the unsetenv(3) system call.

       The  explain_unsetenv_or_die  function  is  intended  to  be  used  in a fashion similar to the following
       example:
              explain_unsetenv_or_die(name);

       explain_unsetenv_or_die - remove an environment variable and report errors

       The  explain_unsetenv_or_die  function  only returns on success, see unsetenv(3) for more information. On
       failure, prints an explanation and exits, it does not return.

       The explain_unsetenv_on_error function always returns the value return by the wrapped unsetenv(3)  system
       call.

unsetenv(3)
               change or add an environment variable

       explain_unsetenv(3)
               explain unsetenv(3) errors

       exit(2) terminate the calling process

       #include <libexplain/unsetenv.h>
       void explain_unsetenv_or_die(const char *name);
       int explain_unsetenv_on_error(const char *name);