Command Line Recursive Find and Replace

Recently I moved a website that used a ton of legacy php code from the clients production server to a development location. After the move was complete I found that the previous developers had been extremely sloppy. Rather than having a single location/file for DB credentials, they had it in 4 places.

After I figured out where all the locations for DB credentials were I started getting Open_Basedir errors. The original developer had hard coded the web root location hundreds of times in hundreds of files. For just a moment I felt just a bit overwhelmed, then I remembered that I have the terminal to solve problems like this.

After a bit of research I came up with the following command to recursively search through the entire codebase. When an instance the old web root is detected it replaces it with the correct one.

grep -rl [search for string] . | xargs sed -i s@[search for string]@[replace with string]@g

Or another example with actual search/replace strings

grep -rl /var/www/vhosts/ . | xargs sed -i s@/var/www/vhosts/

That command breaks down in the following manner.

“grep -rl” searches recursively for the string you specified “/var/www/vhosts/” starting in the current directory “.”, the “-r” option specifies the recursive search, and “-l” specifies that the system should return only the filenames that contain the string.

those results are then piped “| ” into “sed”, the “-i” option specifies that it should make the changes in place. Then the find replace sequence in this case “s@[search for string]@[replace with string]@g”. The “@” signs could be almost any other value, typically they are a “/” but in this case the strings to find and replace both had “/” in each one so it wouldn’t work as the bordering character. So replacing the “/” with “@” helps SED keep on track. It could easily have been a “#” or “$”, just use what you need to depending on your string.

And with that I was home free no more Open_Basedir issues. Thanks to the command line recursive find and replace all those entries didn’t have to be done by hand.

Thanks Linux Shell