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Deleting comments from c-file

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# 1  
Old 11-07-2011
Deleting comments from c-file
hii all,
i am writing a shell script to remove comments from a .c/.cpp file.
i have written script as

Quote:
first="\/\*"
last="\*\/"
sed -i "/$first/,/$last/d" $FILE
sed -i "s/$first.*$last//g" $FILE
sed -i '/^\//d' $FILE # deleting single line comment if start with //
the above script file deletes line between /* and */ also lines starting with //.

but the problems are :
1) i dont want to delete the content between /** and */.

2)sed -i '/^\//d' $FILE ,this command doesnt delete the single line comment if it starts with space or tab. but i want to delete that also.Smilie

please help me out ..
thnx
# 2  
Old 11-07-2011
try with this .. If satisfied with the o/p, then use the -i option in sed
Code:
$ sed 's,/\*\*,,g;s,\*/,,g;s,/\*,,g;s,//,,g' infile.cpp

This User Gave Thanks to jayan_jay For This Post:
yashwantkumar
# 3  
Old 11-07-2011
thanx jayan jay !!
but i dont want to delete those single line comments if it comes after some code
eg. :
function(); // calling a function.

i dont want to delete this comment

---------- Post updated at 02:57 PM ---------- Previous update was at 02:27 PM ----------

Quote:
sed 's,/\*\*,,g;s,\*/,,g;s,/\*,,g;s,//,,g' infile.cpp
its also deleting lines with between /** and */
# 4  
Old 11-07-2011
Post some contents of your input file and expected output ..
# 5  
Old 11-07-2011
test.c
Quote:
#include<stdio.h> //header
#include<stdlib.h> //header
/** print function */
print()
{
printf("hello all");
//printf("hiii");
}
/** main function
*/
int main()
{
//in main function
/*
printf("hello all");
*/
print(); // calling print
}
expected output:
Quote:
#include<stdio.h> //header
#include<stdlib.h> //header
/** print function */
print()
{
printf("hello all");
}
/** main function
*/
int main()
{
print(); // calling print
}
# 6  
Old 11-07-2011
based on your input file ..
Code:
$ sed '/^\/\//d;/^\/\*$/,/^\*\//d' infile.cpp

This User Gave Thanks to jayan_jay For This Post:
yashwantkumar
# 7  
Old 11-07-2011
thank you very much !! ..
this script is working. but if there is any tab or space is there before single line comment "//" or /* its not deleting that.
also its not deleting lines between
/* */ If it is used in same line i.e. /* HELLO */ this line not getting deleted.(i haven't put that case, its my mistake.)
thanks for your kind help !
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