![]() |
|
|
|
|
Issue Type:
|
![Bug]() Bug
|
|
Assignee:
|
Jesse Glick
|
|
Components:
|
durable-task-plugin |
|
Created:
|
07/Nov/14 11:35 PM
|
|
Description:
|
durable task step currently uses nohup to launch a durable process. But if Jenkins is started from an interactive terminal and the user presses Ctrl+C, the forked process is still gone. So far we've blushed it off saying this is not how Jenkins is typically run. That may be true, but it is also a perfectly reasonable way to run Jenkins, for example for the first time evaluation.
The reason these processes get killed with Ctrl+C is because shell sends SIGINT to all the processes in the process group (source). In looking at nohup.c, nohup only ignores SIGHUP. You can also run a command like nohup sleep 30 from the command line. hit Ctrl+C, and observe that the sleep 30 process gets killed.
The root problem is that nohup is a poor way to isolate a child process. Specifically, it doesn't put the process into a new process group, so it's vulnerable to any signal sent to the entire process group (of which Ctrl+C is one.) setsid is a better way of doing this. This puts the process into a new session (hence also new process group.) So no group-wide signal will get to the child process.
See Wikipedia process group page for interaction of signals, process groups, and sessions.
|
|
Project:
|
Jenkins
|
|
Priority:
|
![Minor]() Minor
|
|
Reporter:
|
Kohsuke Kawaguchi
|
|
|
|
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators.
For more information on JIRA, see: http://www.atlassian.com/software/jira
|
--
You received this message because you are subscribed to the Google Groups "Jenkins Issues" group.
To unsubscribe from this group and stop receiving emails from it, send an email to
jenkinsci-issues+unsubscr...@googlegroups.com.
For more options, visit
https://groups.google.com/d/optout.
