* Makefile: Add rules to build and run tst-atfork2 test.
* tst-atfork2.c: New file.
* tst-atfork2mod.c: New file.
* sysdeps/unix/sysv/linux/unregister-atfork.c
(__unregister_atfork): Free the memory allocated for the handlers
after removing them from the lists.
* sysdeps/unix/sysv/linux/register-atfork.c: Define memeory
cleanup function.
* tst-atfork1.c (do_test): Wait for the child we forked.
Report error in child.
* sysdeps/unix/sysv/linux/fork.c (__libc_fork): Fix comment.
Allan McRae
Joseph Myers
Paul Eggert
Ulrich Drepper