Redirecting NSLog with NSLogConsole

UPDATE check out Redirecting NSLog to a file for just capturing NSLog.

NSLogConsole captures NSLog data (from stderr) and redirects it to a console. It still forwards it to XCode's and also appears in I've redirected to an html console, but you can do pretty much anything with the data : save it to a file, mail it, discard it, filter it …

Image:Redirecting NSLog to a console.png

Sample code



  • Copy NSLogConsole.(m h html xib) in your project
  • Add #define NSLog(args...) NSLog(args), NSLogPostLog(__FILE__, __LINE__) to your project's precompiled header
  • Start it with [NSLogConsole sharedConsole] to capture messages, open it with [[NSLogConsole sharedConsole] open]

Thanks to …

2008 08 17

wow, great tool...thx!!

is there some sort of restriction to the source? or is it public domain?


Patrick Geiller
2008 08 17

MIT license. Use freely !

Right now, launching from the Finder blocks on reading … works fine in XCode and Terminal. So don't use in production code :) Somehow stderr doesn't behave the same from Finder and from XCode. Any ideas ?

John McLaughlin
2008 08 18

Brilliant! This is really nicely done!

Frank Hintsch
2010 10 29

Thanks for this wonderful peace of code. While testing I found that -init of NSLogConsole is called twice: 1st by NIB-Loader and 2nd by -sharedConsole.

Bronte Deng
2013 09 18


I run your code, in my prj. Some error comes up for webview didnot load html file before invoking it.

So I add some code below:

In -[logData:file:lineNumber:]

if (![webView isWebViewLoaded]) {


In NSLogConsoleView - (BOOL)isWebViewLoaded;

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