2015-09-19 21:36:28 +0100, Stephane Chazelas: > 2015-09-18 16:14:39 +0100, Stephane Chazelas: > [...] > > In: > > > > bash -c 'sh -c "trap exit INT; sleep 10; :"; echo hi' > > > > If I press Ctrl-C, I still see "hi". > [...] > > Jilles provided with the explanation at > http://unix.stackexchange.com/a/230731 > > with a link to: > http://www.cons.org/cracauer/sigint.html [...]
Note that bash (and ksh, contrary to FreeBSD sh) is not consistent in its handling of that "WCE" (for "wait and cooperative exit") approach in that pressing ^C in: bash -c ' var=$(sh -c "trap \"\" INT; sleep 3; echo result) echo "$var" ' kills bash, leaving the "sh" and "sleep" running unattended in background. Same for: bash -O lastpipe -c ' sh -c "trap \"\" INT; sleep 3; echo test" | read var; echo done' One could also argue, that to be consistent, SIGTSTP and SIGQUIT should be treated similarly (strangely enough http://www.cons.org/cracauer/sigint.html doesn't mention SIGTSTP). I'm not sure I prefer that WCE approach over WUE. Wouldn't it be preferable that applications that intercept SIGINT/QUIT/TSTP for anything other than clean-up before exit/suspend implement job control themselves instead (like vi's :! should create a process group and make that the foreground process group of the terminal so pressing ^C in sh -c vi, :!sleep 10, only sends the SIGINT to sleep)? -- Stephane
