Hello,

In my app I need to determine if some app if properly codesigned. To do this I 
just invoke "/usr/bin/codesign" and analyse return value. To invoke it I use 
NSTask and launch it in background thread. Everything works fine excepts 
strange crash I get sometimes from our customers. While NSTask is waiting for 
command to finish (waitUntilExit) UI starts to update in background thread... 
which causes crashes. I now that's improper to do any UI related stuff in 
background threads. And I don't force UI update explicitly.

But why it's get updated while waiting?

Part of stack trace of crashed thread:

<skipped and crash here>
19  com.apple.AppKit                    0x915e8d40 -[NSWindow displayIfNeeded]  
 204
20  com.apple.Foundation                0x93b6d9d5 __NSFireDelayedPerform   537
21  com.apple.CoreFoundation            0x95634adb __CFRunLoopRun   8059
22  com.apple.CoreFoundation            0x95632464 CFRunLoopRunSpecific   452
23  com.apple.CoreFoundation            0x95632291 CFRunLoopRunInMode   97
24  com.apple.Foundation                0x93be6805 -[NSConcreteTask 
waitUntilExit]   273
<skipped>

NSTask launching code:

        // create task and pipe objects
        NSTask *task = [[NSTask alloc] init];
        NSPipe *outputPipe = [[NSPipe alloc] init];
        NSPipe *errorPipe = [[NSPipe alloc] init];

        // setup binary and arguments
        [task setLaunchPath:cmd];
        [task setStandardOutput:outputPipe];
        // and all error output goes to our pipe, not console
        [task setStandardError:errorPipe];
        [task setArguments:args];
        
        // launch task
        [task launch];

        [task waitUntilExit];
        
        [[errorPipe fileHandleForReading] closeFile];
        [[outputPipe fileHandleForReading] closeFile];
        terminationStatus = [task terminationStatus];
        [task terminate];         // just in case


Thanks for your help,
Vera Tkachenko_______________________________________________

Cocoa-dev mailing list (Cocoa-dev@lists.apple.com)

Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com

Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com

This email sent to arch...@mail-archive.com

Reply via email to