From: Roland McGrath <roland@redhat.com>
Date: Fri, 18 Jul 2008 00:25:10 +0000 (+0000)
Subject: 2008-07-03  Jan Kratochvil  <jan.kratochvil@redhat.com>
X-Git-Tag: v4.5.18~54
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=41c48227a86a176da333f713d5047240885f25cc;p=strace

2008-07-03  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Trace even VFORK on -f on all the platforms.
	* strace.1 <-f>: Describe Linux catches new children immediately.
	<-F>: Make the option obsolete.  Move the SunOS VFORK comment to the
	`-f' option description.
	* defs.h (followvfork): Declaration removed.
	* strace.c (followvfork): Variable removed.
	(main) <-F>: Merge with the `-f' option.
	(trace): Make !FOLLOWVFORK unconditional.
	* process.c (internal_fork): Make !FOLLOWVFORK unconditional.
---

diff --git a/defs.h b/defs.h
index 0ac733f3..cf21c048 100644
--- a/defs.h
+++ b/defs.h
@@ -434,7 +434,7 @@ struct xlat {
 
 extern struct tcb **tcbtab;
 extern int *qual_flags;
-extern int debug, followfork, followvfork;
+extern int debug, followfork;
 extern int dtime, cflag, xflag, qflag;
 extern int acolumn;
 extern unsigned int nprocs, tcbtabsize;
diff --git a/process.c b/process.c
index 63122139..a2109fe3 100644
--- a/process.c
+++ b/process.c
@@ -989,8 +989,7 @@ struct tcb *tcp;
 #ifdef SYS_vfork
 	if (known_scno(tcp) == SYS_vfork) {
 		/* Attempt to make vfork into fork, which we can follow. */
-		if (!followvfork ||
-		    change_syscall(tcp, SYS_fork) < 0)
+		if (change_syscall(tcp, SYS_fork) < 0)
 			dont_follow = 1;
 	}
 #endif
diff --git a/strace.1 b/strace.1
index aa79d6e8..18cd5ae1 100644
--- a/strace.1
+++ b/strace.1
@@ -232,7 +232,9 @@ itself on the standard error.
 Trace child processes as they are created by currently traced
 processes as a result of the
 .BR fork (2)
-system call.  The new process is
+system call.
+.IP
+On non-Linux platforms the new process is
 attached to as soon as its pid is known (through the return value of
 .BR fork (2)
 in the parent process). This means that such children may run
@@ -240,13 +242,17 @@ uncontrolled for a while (especially in the case of a
 .BR vfork (2)),
 until the parent is scheduled again to complete its
 .RB ( v ) fork (2)
-call.
+call.  On Linux the child is traced from its first instruction with no delay.
 If the parent process decides to
 .BR wait (2)
 for a child that is currently
 being traced, it is suspended until an appropriate child process either
 terminates or incurs a signal that would cause it to terminate (as
 determined from the child's current signal disposition).
+.IP
+On SunOS 4.x the tracing of
+.BR vfork s
+is accomplished with some dynamic linking trickery.
 .TP
 .B \-ff
 If the
@@ -258,16 +264,8 @@ where pid is the numeric process id of each process.
 This is incompatible with -c, since no per-process counts are kept.
 .TP
 .B \-F
-Attempt to follow
-.BR vfork s.
-(On SunOS 4.x, this is accomplished with
-some dynamic linking trickery.)
-Otherwise,
-.BR vfork s
-will
-not be followed even if
-.B \-f
-has been given.
+This option is now obsolete and it has the same functionality as
+.BR -f .
 .TP
 .B \-h
 Print the help summary.
diff --git a/strace.c b/strace.c
index 341ed04a..0cbe3228 100644
--- a/strace.c
+++ b/strace.c
@@ -78,7 +78,7 @@
 #endif
 #endif
 
-int debug = 0, followfork = 0, followvfork = 0;
+int debug = 0, followfork = 0;
 int dtime = 0, cflag = 0, xflag = 0, qflag = 0;
 static int iflag = 0, interactive = 0, pflag_seen = 0, rflag = 0, tflag = 0;
 
@@ -659,12 +659,11 @@ main(int argc, char *argv[])
 		case 'd':
 			debug++;
 			break;
+		case 'F':
+			/* Obsoleted, acts as `-f'.  */
 		case 'f':
 			followfork++;
 			break;
-		case 'F':
-			followvfork++;
-			break;
 		case 'h':
 			usage(stdout, 0);
 			break;
@@ -2261,7 +2260,7 @@ trace()
 		/* Look up `pid' in our table. */
 		if ((tcp = pid2tcb(pid)) == NULL) {
 #ifdef LINUX
-			if (followfork || followvfork) {
+			if (followfork) {
 				/* This is needed to go with the CLONE_PTRACE
 				   changes in process.c/util.c: we might see
 				   the child's initial trap before we see the