Article View: comp.unix.shell
Article #99How to send a signal to a shell script? (ANSWER)
From: Kees Huizing
Date: Wed, 22 Jul 1992 12:10
Date: Wed, 22 Jul 1992 12:10
36 lines
1733 bytes
1733 bytes
Thanks to Michael Cook <mcook@merlin.dev.cdx.mot.com>, I know the answer to my question. Summary of the problem: A signal is sent to a shell script with process id 12345 and job number 1 (in csh) that is currently executing a sleep command. The signal USR1 seems not to arrive when sent with the command: kill -30 12345 It does arrive, however, when sent with kill -30 %1 How is this possible, and how can I interrupt the script in case the job number is not accessible and I don't want to signal the sleep process explicitly? The answer is that the first command sends a signal to the script process *only*, whereas the second sends it to the process *group* (all processes dependent on 12345). As long as the sleep is executing, the shell script process is suspended and buffers the incoming signals. And the intention was abort the sleep process and ahndle the signal immediately. Solution: use kill -30 -12345 This to me unknown (SysV?) feature of the kill command sends the signal to every member of the process group. It works on my Sun. Thanks to everyone who thought about this, especially to Michael. Kees -- Kees Huizing - Eindhoven Univ of Techn - Dept Math & Comp Sc - The Netherlands e-mail: keesh@win.tue.nl telephone: +31-40-474120 fax: +31-40-463992
Technical Details
Message-ID:
<3714@svin02.info.win.tue.nl>Path:
arc1-ca.pugleaf.net!sparky!uunet!mcsun!sun4nl!tuegate.tue.nl!svin02!wsinti01!keeshReferences:
<3700@svin02.info.win.tue.nl>Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!sparky!uunet!mcsun!sun4nl!tuegate.tue.nl!svin02!wsinti01!keesh From: keesh@wsinti01.info.win.tue.nl (Kees Huizing) Newsgroups: comp.unix.shell Subject: How to send a signal to a shell script? (ANSWER) Message-ID: <3714@svin02.info.win.tue.nl> Date: 22 Jul 92 12:10:11 GMT References: <3700@svin02.info.win.tue.nl> Sender: news@svin02.info.win.tue.nl Reply-To: keesh@info.win.tue.nl Lines: 36