Add thread-safety to libc, so that libc_r will build (on i386 at least).

All POSIX libc api now there (to P1003.1c/D10)
  (more md stuff is needed for other libc/arch/*)
  (setlogin is no longer a special syscall)
Add -pthread option to gcc (that makes it use -lc_r and -D_POSIX_THREADS).
Doc some re-entrant routines
Add libc_r to intro(3)
dig() uses some libc srcs and an extra -I was needed there.
Add more md stuff to libc_r.
Update includes for the pthreads api
Update libc_r TODO

1 files changed, 10 insertions, 1 deletions

diff --git a/src/lib/libc/stdlib/exit.c b/src/lib/libc/stdlib/exit.c
index e358c94fd6..bc7fd395ca 100644
--- a/src/lib/libc/stdlib/exit.c
+++ b/src/lib/libc/stdlib/exit.c
@@ -32,7 +32,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: exit.c,v 1.2 1996/08/19 08:33:30 tholo Exp $";
+static char *rcsid = "$OpenBSD: exit.c,v 1.3 1998/11/20 11:18:50 d Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <stdlib.h>
@@ -42,6 +42,15 @@ static char *rcsid = "$OpenBSD: exit.c,v 1.2 1996/08/19 08:33:30 tholo Exp $";
 void (*__cleanup)();
 
 /*
+ * This variable is zero until a process has created a thread.
+ * It is used to avoid calling locking functions in libc when they
+ * are not required. By default, libc is intended to be(come)
+ * thread-safe, but without a (significant) penalty to non-threaded
+ * processes.
+ */
+int     __isthreaded    = 0;
+
+/*
  * Exit, flushing stdio buffers if necessary.
  */
 void