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Find that error
Typically, when we're setting up new sites or scripts, we'll encounter some kind of error. To monitor your lighttpd error log for example:
tail -f ~/var/log/lighttpd.error.log
Tail is a command that will display the last few lines of any text file. The -f flag will open tail and keep the log file open - then we go to our browser and refresh, hopefully we'll see the relevant error in the tail output.
Note, to get out of tail -f, press the Ctrl+C key combination.
Some useful variations:
tail -n 100 ~/var/log/lighttpd.error.log
This will display the last 100 lines of the error log on your console. To make it even easier to scan those lines, you can pipe (|) the output to the "less" command and then be able to scroll up and down:
tail -n 100 ~/var/log/lighttpd.error.log | less
Less is handy as a "paging" program for the command line; instead of dumping all 100 lines to your console and scrolling up, less lets you use the up / down arrow keys to scroll up and down. To scroll down a screen at a time, press the "v" key... to scroll up a screen at a time, press the "b" key.
Note, to exit the less program, press the "q" key.