On Tue, Mar 23, 2010 at 7:46 PM, Eric Blake <ebl...@redhat.com> wrote: > On 03/23/2010 01:29 AM, Siddhesh Poyarekar wrote: >> Steps to Reproduce: >> 1. trap '' SIGINT >> 2. exec bash >> 3. trap -p > > POSIX states: > > "Signals that were ignored on entry to a non-interactive shell cannot be > trapped or reset, although no error need be reported when attempting to > do so. An interactive shell may reset or catch signals ignored on entry." > http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap > > I see no bug - bash is within its rights to pretend that an inherited > ignored SIGINT has no trap setting, seeing as how the user cannot modify > that through any use of trap. That is, 'trap -p' is designed to output > the text that will restore traps to their normal state, but since there > is no way to change the state of SIGINT from being ignored, there is > nothing needed in the output. >
Thanks for that explanation. I guess we can also detect if a signal is being ignored by trying to set a trap for that signal and verify that it has not been set. This was my original problem and I went about trying to fix it in code rather than reading the docs carefully :) -- Siddhesh Poyarekar http://siddhesh.in
