问题
Please consider this bash-script:
#!/bin/bash
trap '' INT
echo sleep:
sleep 5
echo rsync:
rsync -a /usr/lib /var/tmp
Trying to interrupt sleep with ctrl-c fails, as expected. But rsync is interruptible (the order of sleep & rsync doesn't matter)? Any ideas are welcome!
Edit: Found a difference: rsync itself starts 2 child procs (client/server, which produce the 2 error msgs, i assume), and these seem not to inherit the 'ignorance' of its parent. Must dive into bash sources and find out how trap is working...
回答1:
Have you tried using rsync with --no-detach as advised in the SO question bash not trapping interrupts during rsync subshell/exec statements?
回答2:
It's pretty clear from experimentation that rsync behaves like other tools such as ping and do not inherit signals from the calling Bash parent.
So you have to get a little creative with this and do something like the following:
$ cat rsync.bash
#!/bin/sh
set -m
trap '' SIGINT SIGTERM EXIT
rsync -avz LargeTestFile.500M root@host.mydom.com:/tmp/. &
wait
echo FIN
Now when I run it:
$ ./rsync.bash
X11 forwarding request failed
building file list ... done
LargeTestFile.500M
^C^C^C^C^C^C^C^C^C^C
sent 509984 bytes received 42 bytes 92732.00 bytes/sec
total size is 524288000 speedup is 1027.96
FIN
And we can see the file did fully transfer:
$ ll -h | grep Large
-rw-------. 1 501 games 500M Jul 9 21:44 LargeTestFile.500M
How it works
The trick here is we're telling Bash via set -m to disable job controls on any background jobs within it. We're then backgrounding the rsync and then running a wait command which will wait on the last run command, rsync, until it's complete.
We then guard the entire script with the trap '' SIGINT SIGTERM EXIT.
References
- https://access.redhat.com/solutions/360713
- https://access.redhat.com/solutions/1539283
- Delay termination of script
来源：https://stackoverflow.com/questions/13570680/bash-trap-wont-ignore-signal