Shell / Sed Script To Remove All Comments From C Program

Run this script as follows:
cat file.c | ./script.sh
sample file.c:

#include<stdio.h>
/* This is a test program 
 * Version 1.0
 * */
int main(){
        printf("This is a test");
        /* now exit */
}

Sample output:

#include<stdio.h>
 
int main(){
        printf("This is a test");
 
}

Sed Script


#!/bin/sed -f
# Simple Sed Program to remove all comments from c program
# --------------------------------------------------------------------
# This is a free shell script under GNU GPL version 2.0 or above
# Copyright (C) 2005 nixCraft project.
# Feedback/comment/suggestions : http://cyberciti.biz/fb/
# -------------------------------------------------------------------------
# This script is part of nixCraft shell script collection (NSSC)
# Visit http://bash.cyberciti.biz/ for more information.
# -------------------------------------------------------------------------
# if no /* get next
/\/\*/!b
# here we've got an /*, append lines until get the corresponding
# */
:x
/\*\//!{
N
bx
}
# delete /*...*/
s/\/\*.*\*\///

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1 comment… add one
  • vlp Aug 18, 2010 @ 11:53

    Does not work for me with the following:
    +++/*—-*/+++/*—-
    –*/+++

    (should give +++++++++)

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