I found myself need to join two lines in a text file if the second line starts with a certain string the other day. I know this is a place where scripting language and tools like sed and awk shine.
I ended up writing a short Perl script to do that. A google search led me to this sed FAQ page which shows how to do it in a sed one liner:
In this example, we want to match the string “<<=" at the beginning of one line, bring that line up to the end of the line before it, and replace the string with a single space:sed -e :a -e ‘$!N;s/n<<=/ /;ta' -e 'P;D' file # all seds
You got to love swiss army knife like this.