Linux Search And Replace Source: http://stackoverflow.com/a/8588807/2560557

gistfile1.md

For the file file.txt:

sed -i 's/abc/abcd/g' file.txt

For all files in the current folder:

find . -maxdepth 1 -type f -exec sed -i 's/abc/abcd/g' {} \;

For the files in the current directory and all subdirectories:

find . -type f -exec sed -i 's/abc/abcd/g' {} \;