diff -rc3p strace-4.4/strace.c /tmp/strace-4.4/strace.c
*** strace-4.4/strace.c	Fri Aug  3 05:43:35 2001
--- /tmp/strace-4.4/strace.c	Fri Feb 22 12:40:26 2002
*************** int sig;
*** 993,1050 ****
  #ifdef LINUX
  	/*
  	 * Linux wrongly insists the child be stopped
! 	 * before detaching.  Arghh.  We go through hoops
! 	 * to make a clean break of things.
  	 */
! #if defined(SPARC)
! #undef PTRACE_DETACH
! #define PTRACE_DETACH PTRACE_SUNDETACH
! #endif
! 	if ((error = ptrace(PTRACE_DETACH, tcp->pid, (char *) 1, sig)) == 0) {
! 		/* On a clear day, you can see forever. */
! 	}
! 	else if (errno != ESRCH) {
! 		/* Shouldn't happen. */
! 		perror("detach: ptrace(PTRACE_DETACH, ...)");
! 	}
! 	else if (kill(tcp->pid, 0) < 0) {
! 		if (errno != ESRCH)
! 			perror("detach: checking sanity");
! 	}
! 	else if (kill(tcp->pid, SIGSTOP) < 0) {
! 		if (errno != ESRCH)
  			perror("detach: stopping child");
! 	}
! 	else {
! 		for (;;) {
! 			if (waitpid(tcp->pid, &status, 0) < 0) {
! 				if (errno != ECHILD)
! 					perror("detach: waiting");
! 				break;
! 			}
! 			if (!WIFSTOPPED(status)) {
! 				/* Au revoir, mon ami. */
! 				break;
! 			}
! 			if (WSTOPSIG(status) == SIGSTOP) {
! 				if ((error = ptrace(PTRACE_DETACH,
! 				    tcp->pid, (char *) 1, sig)) < 0) {
! 					if (errno != ESRCH)
! 						perror("detach: ptrace(PTRACE_DETACH, ...)");
! 					/* I died trying. */
  				}
- 				break;
  			}
! 			if ((error = ptrace(PTRACE_CONT, tcp->pid, (char *) 1,
! 			    WSTOPSIG(status) == SIGTRAP ?
! 			    0 : WSTOPSIG(status))) < 0) {
  				if (errno != ESRCH)
! 					perror("detach: ptrace(PTRACE_CONT, ...)");
! 				break;
  			}
  		}
  	}
! #endif /* LINUX */
  
  #if defined(SUNOS4)
  	/* PTRACE_DETACH won't respect `sig' argument, so we post it here. */
--- 993,1096 ----
  #ifdef LINUX
  	/*
  	 * Linux wrongly insists the child be stopped
! 	 * before detaching.  This creates numerous headaches
! 	 * as the process we are tracing may be running.
! 	 *
! 	 * First stop the process by sending it a SIGSTOP
! 	 * signal.  If the process is already stopped, this
! 	 * is harmless.
! 	 *
! 	 * Once the process is stopped we have to make sure it
! 	 * received the SIGSTOP (it may have received a SIGTRAP or
! 	 * other signal).  If it did not receive the SIGSTOP, 
! 	 * restart the process and try again. 
! 	 *
! 	 * Once stopped with a SIGSTOP, we can detach from the
! 	 * process via PTRACE_DETACH. 
! 	 *
  	 */
! 	
! 
! 	for (;;) {
! 
! 		if (kill(tcp->pid, 0) < 0) {
! 			if (errno != ESRCH)
! 				perror("detach: checking sanity");
! 		}
! 		else if (kill(tcp->pid, SIGSTOP) < 0) {
! 			if (errno != ESRCH)
  			perror("detach: stopping child");
! 		}
! 
! 		/*
! 		 * At this point the child should be stopped.  Try to
! 		 * wait on it so we can get its stop status.
! 		 */
! 		if (waitpid (tcp->pid, &status, WUNTRACED) < 0) {
! 			if (errno != ECHILD) {
! 				perror("detach: waiting");
! 			} else {
! 
! 				/*
! 				 * Try again, this time with the __WCLONE
! 				 * flag.  Note we may get notifications
! 				 * for other processes/threads!
! 				 */
! 				errno = 0;
! 				while (1) {
! 					int x;
! 
! 					x = waitpid (-1, &status, __WCLONE);
! 					if (x == tcp->pid || x < 0 || errno != 0)
! 						break;
  				}
  			}
! 
! 			if (errno) {
! 				perror ("Unable to wait on inferior");
! 				return -1;
! 			}
! 		}
! 		
! 		/*
! 		 * At this point we have wait status for the
! 		 * inferior.  If it did not stop, then all 
! 		 * bets are off.
! 		 */
! 		if (!WIFSTOPPED(status)) {
! 			/* Au revoir, mon ami. */
! 			break;
! 		}
! 
! 		/*
! 		 * If the process/thread has stopped with a
! 		 * SIGSTOP, then we can continue and detach
! 		 * with PTRACE_DETACH.
! 		 */
! 		if (WSTOPSIG(status) == SIGSTOP) {
! 			if ((error = ptrace(PTRACE_DETACH,
! 			    tcp->pid, (char *) 1, sig)) < 0) {
  				if (errno != ESRCH)
! 					perror("detach: ptrace(PTRACE_DETACH, ...)");
! 				/* I died trying. */
  			}
+ 			break;
+ 		}
+ 
+ 		/*
+ 		 * The process/thread did not stop with a SIGSTOP,
+ 		 * so let it continue and try again to stop it with
+ 		 * a SIGSTOP.
+ 		 */
+ 		if ((error = ptrace(PTRACE_CONT, tcp->pid, (char *) 1,
+ 		    WSTOPSIG(status) == SIGTRAP ?
+ 		    0 : WSTOPSIG(status))) < 0) {
+ 			if (errno != ESRCH)
+ 				perror("detach: ptrace(PTRACE_CONT, ...)");
+ 			break;
  		}
  	}
! #endif
  
  #if defined(SUNOS4)
  	/* PTRACE_DETACH won't respect `sig' argument, so we post it here. */