#ifdef linux

I use the mighty vim editor for most of my coding. I have a heavily customized setup which has evolved over quite a few years. However, it is by no means a static setup as I keep finding new scripts and tricks (and of course Bram keeps on adding extra goodness with each release). Recently, I was hacking through a lot of C code containing lots of debug cruft (log function calls, commented out bits and pieces, etc). The problem was I couldn't get a feel for the code as all the debug was too distracting. The question popped into my head, "can I hide all this stuff?" A number of folk have come up with ways to "hide" the data you don't want to see in Vim using folds (" :help fold " in Vim). However, that wasn't what I wanted as folds also introduce their own "visual noise". I just wanted this stuff gone . What I came up with is a complete hack, but it suited my purpose rather well: I changed the colour of the regex's matching the ...

Yesterday, whilst hacking on a particularly large Upstart C file in the awesome vim editor, I inadvertently 'put' a huge amount of data, caused by my mis-specifying the marks when I had originally yanked the text. Still unaware of the problem, I then compounded the problem nicely by continuing to make further changes to the file and dug myself an even bigger hole by saving the file and exiting vim. Attempting to compile the now totally invalid code resulted in a seething mass of mocking gcc warnings until it eventually gave up in disgust. Thankfully, I was taking regular backups with rsnapshot and I had the bzr branch history to fall back on. But it still took some time to perform the 3-way diff and get back to my latest changes. Later on, we had our weekly IRC meeting in #ubuntu-meeting . I use irssi and as I pasted my weekly status update, since I was pasting more than a single line, irssi gave me a helpful warning and the option to either proceed, or abort the mult...

This is a useful trick to avoid creating lots of intermediate temporary files when you're trying to compare two files that are almost the same, but which have some fields which are guaranteed to be different. Classic examples of this are two log files that have almost the same data in them, but where every line in these files is prefixed by a pesky timestamp which is different between the two files. bash process substitution (using named pipes) to the rescue! Let's assume we have two files " file1.log " and " file2.log " and the first six space-separated fields comprise a timestamp. To ignore those fields and just diff the log file contents we can do this: $ diff <(cut -d" " -f7- /tmp/file1.log) <(cut -d" " -f7- /tmp/file2.log) But why limit yourself to a textual diff. Go graphical if you prefer: $ meld <(cut -d" " -f7- /tmp/file1.log) <(cut -d" " -f7- /tmp/file2.log) This technique can be employed ...