Permanently configuring LLDB (in Xcode 4.3.2) not to stop on signals

Question

I'm trying to get LLDB (running in Xcode 4.3.2 with an OS X application) to not stop on certain signals. If I enter

process handle SIGUSR2 -n true -p true -s false

on the debugging console it works fine and LLDB no longer stops on SIGUSR2.

However, if I put

command process handle SIGUSR2 -n true -p true -s false

into ~/.lldbinit it seems to be ignored. Other commands in this file (e.g. alias) work fine.

How can I make LLDB never stop on certain signals?

Solution

In case anyone else ever has this question, I finally solved it by adding a breakpoint in NSApplicationMain() (for plain C programs, main() would of course work as well).

I set the breakpoint action to process handle SIGUSR2 -n true -p true -s false, and enabled the "Automatically continue after evaluating" option.

If anyone has a more elegant solution, I'd be happy to hear.

Comments

[blueberryfields]

I don't think that what you want to do is doable, without an explicit The process is a run-time concept. Maybe there's a useful setting under "settings list" that you can set?

[puzzle]

Thanks, that explains why adding the command to ~/.lldbinit did not work :)

[user500]

Just in case... Don't forget to change symbol to UIApplicationMain for iOS.

[n0minal]

Itworks for me. but after my application freezes. Would this be the true behavior?

[puzzle]

Telling lldb to ignore certain signals should not cause an application to freeze. Where does your application freeze and how?

[brunobowden]

For Swift use "UIApplicationMain"

[Laurent Zubiaur]

You might also just ignore the signal with signal(SIGPIPE, SIG_IGN)

[itMaxence]

Wether you ignore or not the signal will not prevent xcode to stop :( (and btw you should better use sigaction() to ignore a signal)

[itMaxence]

@puzzle could you explain or let a link about the process handle [signal] -n true -p true -s false line? Just for the sake of understanding what I'm copy/pasting :)

[puzzle]

@itMaxence If you enter help process handle in your lldb console, you'll get an explanation of all the possible arguments.

[shallowThought]

In Xcode 13, having a commandline tool as target, setting this breakpoint in ìnt main(...) ...`, I get: "error: invalid target, create a target using the 'target create' command". any hints any one?