#---------- Modifying files in place with [fileinput]----------# % cat a b AAAAA BBBBB % cat modify.py #!/usr/bin/env python import fileinput, sys for line in fileinput.input(sys.argv[1:], inplace=1): print "MODIFIED", line, % echo "XXX" | ./modify.py a b - MODIFIED XXX % cat a b MODIFIED AAAAA MODIFIED BBBBB