chgrep - change oldpatter to newpattern in lines
chgrep [-vlrhin] [-t filename] OLDPATTERN NEWPATTERN [file...]
Chgrep searches the input files (or standard input if no files are named) for oldstring and changes them to newstring. If some file and file.lock exist then chgrep leaves both files unchanged. You can write NEWPATTERN as "NULL" to clear OLDPATTERN, i.e. "chgrep oldstring NULL somefile.c".
Chgrep is much faster than perl or sed (man memcpy, man realloc). If You have huge files which You need to change probably You will need chgrep.
-v Prints to standard output diagnostic informations.
-l Leaves copy of old file unchanged in filename.lock
-r Read all files under each subdirectory, recursively.
-i Ignore differences in case at OLDPATTERN.
-n Treat as a regular character.
-h Print the version number of chgrep to standard output. This version number should be included in all bug reports (see below).
Normally, exit status is 0 if no errors were found, and 1 if some errors were found. The -v option helps to understand the sense of the exit status.
The program is written under GNU GPL Public License.
Email bug reports to firstname.lastname@example.org. Be sure to include the word "chgrep" somewhere in the "Subject:" field.