Learning and Maintaining a Large Inherited Codebase?

An anonymous reader writes "A couple of times in my career, I've inherited a fairly large (30-40 thousand lines) collection of code. The original authors knew it because they wrote it; I didn't, and I don't. I spend a huge amount of time finding the right place to make a change, far more than I do changing anything. How would you learn such a big hunk of code? And how discouraged should I be that I can't seem to 'get' this code as well as the original developers?"pa href="http://ask.slashdot.org/story/10/02/12/2329252/Learning-and-Maintaining-a-Large-Inherited-Codebase?from=rss"img src="http://developers.slashdot.org/slashdot-it.pl?from=rssamp;op=imageamp;style=h0amp;sid=10/02/12/2329252"/a/ppa href="http://ask.slashdot.org/story/10/02/12/2329252/Learning-and-Maintaining-a-Large-Inherited-Codebase?from=rss"Read more of this story/a at Slashdot./ppa href="http://feedads.g.doubleclick.net/~at/ZVb-W3Jsjy4a5W7WTZuOK1lzuoQ/0/da"img src="http://feedads.g.doubleclick.net/~at/ZVb-W3Jsjy4a5W7WTZuOK1lzuoQ/0/di" border="0" ismap="true"/img/abr/a href="http://feedads.g.doubleclick.net/~at/ZVb-W3Jsjy4a5W7WTZuOK1lzuoQ/1/da"img src="http://feedads.g.doubleclick.net/~at/ZVb-W3Jsjy4a5W7WTZuOK1lzuoQ/1/di" border="0" ismap="true"/img/a/pimg src="http://feeds.feedburner.com/~r/Slashdot/slashdotDevelopers/~4/yfpwi-2JtjQ" height="1" width="1"/

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