Debian bug report logs - #1297 nohup doesn't seem to work Package: shellutils ; Reported by: Raul Miller ; 62 days old . ----------------------------------------------------------------------- Message received at debian-bugs: From pixar.com!bruce Sat Sep 2 22:53:44 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sp800-000EuGC; Sat, 2 Sep 95 22:53 PDT Received: from mongo.pixar.com by pixar.com with SMTP id AA05183 (5.67b/IDA-1.5 for bruce@mongo.pixar.com); Sat, 2 Sep 1995 22:53:32 -0700 Received: by mongo.pixar.com (Smail3.1.28.1 #15) id m0sp7zv-000Et0C; Sat, 2 Sep 95 22:53 PDT Message-Id: To: Raul Miller Cc: bruce@Pixar.com, debian-bugs@Pixar.com Subject: Re: Bug#1297: nohup doesn't seem to work In-Reply-To: Your message of "Sat, 02 Sep 1995 23:55:22 PDT." <199509030355.XAA20235@magenta.com> Date: Sat, 02 Sep 1995 22:53:39 -0700 From: Bruce Perens I'm going to close this bug, as it doesn't seem to be a nohup problem. You might play around with "stty -hup", though I don't know if that will work. Bruce ----------------------------------------------------------------------- Acknowledgement sent to Bruce Perens : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1297 ; Package shellutils . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From magenta.com!moth Sat Sep 2 21:00:21 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sp6EG-000Bz5C; Sat, 2 Sep 95 21:00 PDT Received: from magenta.com by pixar.com with SMTP id AA00596 (5.67b/IDA-1.5 for bruce@mongo.pixar.com); Sat, 2 Sep 1995 21:00:08 -0700 Received: (moth@localhost) by magenta.com (8.6.12/8.6.4) id XAA20235; Sat, 2 Sep 1995 23:55:22 -0400 Date: Sat, 2 Sep 1995 23:55:22 -0400 Message-Id: <199509030355.XAA20235@magenta.com> From: Raul Miller Reply-To: Raul Miller To: bruce@Pixar.com Cc: debian-bugs@Pixar.com In-Reply-To: (message from Bruce Perens on Fri, 01 Sep 1995 23:22:27 -0700) Subject: Re: Bug#1297: nohup doesn't seem to work I think this is a red herring. The signal won't get raised if the handler is set to SIG_IGN. Moreover, when I run the simple test below, nohup works correctly. I still suspect something else is getting to the SIGHUP handler in the test you are running. [test deleted.] Ok, perhaps I've completely misdiagnosed what's going on. Here's my situation: I'm trying to run xdos (from dosemu) as root. [suid root doesn't work for some features.] So, I need to respond to the su prompt before I am able to fire up xdos. However, using the "obvious method" of firing up an rxvt (or, if I remember right, an xterm) to run the su has the problem that when the rxvt (or xterm) exits it kills the dos window. nohup won't solve this problem. >From earlier attempts at getting telnet to do rsh like things under X, and from some tests I did before submitting this bug report, I believe that this phenomena is independent of the program I'm running from inside su. It's also independent of su -- sh -c exhibits the same symptoms as su -c. Unfortunately, I'm not going to have access to the machine that has X installed till tuesday, so I can't run any further tests at this time. -- Raul ----------------------------------------------------------------------- Acknowledgement sent to Raul Miller : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1297 ; Package shellutils . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From pixar.com!bruce Fri Sep 1 23:23:44 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0solzU-000EqMC; Fri, 1 Sep 95 23:23 PDT Received: from mongo.pixar.com by pixar.com with SMTP id AA10520 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Fri, 1 Sep 1995 23:23:33 -0700 Received: by mongo.pixar.com (Smail3.1.28.1 #15) id m0solyG-000EppC; Fri, 1 Sep 95 23:22 PDT Message-Id: To: Raul Miller , debian-bugs@Pixar.com Cc: bruce@Pixar.com Subject: Re: Bug#1297: nohup doesn't seem to work In-Reply-To: Your message of "Fri, 01 Sep 1995 18:57:36 PDT." <199509012257.SAA00237@magenta.com> Date: Fri, 01 Sep 1995 23:22:27 -0700 From: Bruce Perens From: Raul Miller > Unlike BSD systems, signals under Linux are reset to their > default behavior when raised. I think this is a red herring. The signal won't get raised if the handler is set to SIG_IGN. Moreover, when I run the simple test below, nohup works correctly. I still suspect something else is getting to the SIGHUP handler in the test you are running. Thanks Bruce Script started on Fri Sep 1 23:17:33 1995 > bash bash$ sleep 100 & [1] 1268 bash$ kill -HUP 1268 bash$ [1]+ Hangup sleep 100 bash$ nohup sleep 100 & [1] 1269 bash$ nohup: appending output to `nohup.out' ps PID TTY STAT TIME COMMAND 135 v01 S 0:01 -tcsh 136 v02 S 0:01 -tcsh 1201 v02 T 0:00 ftp mongo 1259 v02 S 0:00 script 1260 v02 S 0:00 script 1261 pp2 S 0:00 -h -i 1265 pp2 S 0:00 bash 1269 pp2 S N 0:00 sleep 100 1274 pp2 R 0:00 ps bash$ kill -HUP 1269 bash$ kill -HUP 1269 bash$ kill -HUP 1269 bash$ ps PID TTY STAT TIME COMMAND 135 v01 S 0:01 -tcsh 136 v02 S 0:01 -tcsh 1201 v02 T 0:00 ftp mongo 1259 v02 S 0:00 script 1260 v02 S 0:00 script 1261 pp2 S 0:00 -h -i 1265 pp2 S 0:00 bash 1269 pp2 S N 0:00 sleep 100 1275 pp2 R 0:00 ps bash$ exit exit > exit exit Script done on Fri Sep 1 23:18:25 1995 ----------------------------------------------------------------------- Acknowledgement sent to Bruce Perens : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1297 ; Package shellutils . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From magenta.com!moth Fri Sep 1 16:03:43 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0sof7f-000EAvC; Fri, 1 Sep 95 16:03 PDT Received: from magenta.com by pixar.com with SMTP id AA19134 (5.67b/IDA-1.5 for bruce@mongo.pixar.com); Fri, 1 Sep 1995 16:03:30 -0700 Received: (moth@localhost) by magenta.com (8.6.12/8.6.4) id SAA00237; Fri, 1 Sep 1995 18:57:36 -0400 Date: Fri, 1 Sep 1995 18:57:36 -0400 Message-Id: <199509012257.SAA00237@magenta.com> From: Raul Miller Reply-To: Raul Miller To: bruce@Pixar.com Cc: debian-bugs@Pixar.com In-Reply-To: (message from Bruce Perens on Wed, 30 Aug 1995 16:40:47 -0700) Subject: Re: Bug#1297: nohup doesn't seem to work You aren't registering a handler for SIGHUP, are you? That will invalidate the action of "nohup". That makes a certain amount of sense. Hmm, let me check the code for nohup... Ok, you're right in that nohup installs a signal handler then execs the desired program. However, this is a problem under linux. According to the man page: Unlike BSD systems, signals under Linux are reset to their default behavior when raised. In the case I reported, I'd guess that more than one SIGHUP is being delivered to the program allegedly protected by nohup. Basically, this means that it's difficult to come up with a system which pops up a temporary window to prompt for a password to use in running some other program. -- Raul ----------------------------------------------------------------------- Acknowledgement sent to Raul Miller : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1297 ; Package shellutils . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From pixar.com!bruce Wed Aug 30 16:40:49 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0snwkS-000EFQC; Wed, 30 Aug 95 16:40 PDT Received: from mongo.pixar.com by pixar.com with SMTP id AA00111 (5.67b/IDA-1.5 for bruce@mongo.pixar.com); Wed, 30 Aug 1995 16:40:38 -0700 Received: by mongo.pixar.com (Smail3.1.28.1 #15) id m0snwkR-000BgVC; Wed, 30 Aug 95 16:40 PDT Message-Id: X-Mailer: exmh version 1.6.2 7/18/95 To: Raul Miller , debian-bugs@Pixar.com Cc: bruce@Pixar.com Subject: Re: Bug#1297: nohup doesn't seem to work In-Reply-To: Your message of "Wed, 30 Aug 1995 18:47:00 PDT." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 30 Aug 1995 16:40:47 -0700 From: Bruce Perens You aren't registering a handler for SIGHUP, are you? That will invalidate the action of "nohup". Bruce -- -- Attention Ham Radio Operators: For information on "Linux for Hams", read -- the World Wide Web page http://www.hams.com/LinuxForHams, or e-mail to -- info@hams.com . ----------------------------------------------------------------------- Acknowledgement sent to Bruce Perens : Extra info received and forwarded. Full text available. ----------------------------------------------------------------------- Information forwarded to debian-devel@pixar.com : Bug#1297 ; Package shellutils . Full text available. ----------------------------------------------------------------------- Message received at debian-bugs: From tad.micro.umn.edu!rdm Wed Aug 30 15:48:14 1995 Return-Path: Received: from pixar.com by mongo.pixar.com with smtp (Smail3.1.28.1 #15) id m0snvvZ-0006FtC; Wed, 30 Aug 95 15:48 PDT Received: from rdm.legislate.com ([192.77.155.13]) by pixar.com with SMTP id AA26108 (5.67b/IDA-1.5 for debian-bugs-pipe@mongo.pixar.com); Wed, 30 Aug 1995 15:48:00 -0700 Received: by rdm.legislate.com id (Debian /\oo/\ Smail3.1.29.1 #29.33); Wed, 30 Aug 95 18:47 EDT Message-Id: Date: Wed, 30 Aug 95 18:47 EDT From: Raul Miller To: debian-bugs@pixar.com Subject: nohup doesn't seem to work Package: shellutils Version: 1.12 Revision: 3 I can reliably generate a HUP signal in a program run by nohup. The general approach is: rxvt -e sh -c 'nohup testprog & sleep 5' [The sleep is an arbitrary mechanism to allow the testprog to register its signal handlers before the HUP is delivered.] -- Raul ----------------------------------------------------------------------- Acknowledgement sent to Raul Miller : New bug report received and forwarded. Full text available. ----------------------------------------------------------------------- Report forwarded to debian-devel@pixar.com : Bug#1297 ; Package shellutils . Full text available. ----------------------------------------------------------------------- Ian Jackson / iwj10@thor.cam.ac.uk , with the debian-bugs tracking mechanism This page last modified 07:43:01 GMT Wed 01 Nov