found 288320 dash/0.5.6.1-1~exp2 clone 288320 -1 retitle -1 dash.1: please document handling of SIGTSTP in command sequences severity -1 minor severity 288320 wishlist tags 288320 + confirmed quit
Hi Larry, Larry Doolittle wrote: > If we wanted to send a consistent message to all Debian shell users, > we could add to the dash BUGS section something related to the bash text > "Compound commands and command sequences of the form `a ; b ; c' are > not handled gracefully when process suspension is attempted. When a > process is stopped, the shell immediately executes the next command in > the sequence. It suffices to place the sequence of commands between > parentheses to force it into a subshell, which may be stopped as a unit." > (which could be improved; it's kinda long, and doesn't mention the return > value used in that case) That sounds like an excellent idea. As far as I can tell, POSIX doesn't speak to this (and an interpretation would be nice; see http://austingroupbugs.net/ if you'd like to pursue that). The description of "set -m" seems to have been written with the expectation that each command in an interactive shell is a single pipeline. ksh93 behaves as follows: | ksh93$ echo hi; sleep 10; echo $? | hi | ^Z[1] + Stopped echo hi; sleep 10; echo $? | ksh93$ fg | echo hi; sleep 10; echo $? | 0 mksh ignores the SIGTSTP signal. bash and dash behave as you describe, by continuing a compound command when one of its components has stopped. I'm keeping this bug as a wishlist because it would be nice to adopt the ksh behavior. Thanks for writing, Jonathan -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
