Is there any way to watch a variable in Xcode using LLDB ? Or is this only possible with GDB ?
I'm trying to use the command watchpoint set variable but I get the message:
invalid command 'watchpoint set'
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the Reverend
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Watchpoints are supported for iOS and Mac OS X debugging as of Xcode 4.5. To set a breakpoint on a variable named foo, do
(lldb) watchpoint set variable foo
you can always use the shortest unambiguous name for commands in the lldb console so
(lldb) w s v foo
would also work here.
In Xcode, in the locals window you can right-click/control-click on variables and you'll have an option to set a watchpoint on it.
The current arm and x86 cpus only support 4 watchpoints being active at the same time.
Jason Molenda
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Thank you for letting us know that they have been activated . I have checked on XCode 4.5 and it works! – the Reverend Oct 17 '12 at 14:43
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and where can these watched variables be seen? – Tudor Nov 12 '12 at 09:38
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`watch list` will list all watched variables. See `help watch` for other supported subcommands. – Jason Molenda Nov 12 '12 at 11:27
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Try using
frame variable -w
instead. The 'watchpoint set' command is in lldb's development branch, and will likely make it in to a future version of Xcode.
For example:
frame variable -w write myvar
EDIT: The watch set variable syntax mentioned in the original post is now supported in lldb in XCode 4.4 and greater.
leecbaker
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A reverence which includes the `watch set var -w write global_var` format: http://lldb.llvm.org/lldb-gdb.html – bshirley Oct 01 '12 at 23:32