grep -v '^#' samba.conf
here -v is for inverse
ie -v, --invert-match
Invert the sense of matching, to select non-matching lines.
Will print all lines EXCEPT those that begin with a # char.
you can change the comment char to whatever you wish.
egrep -v '^(;|#|//)' filelist
If you have more than one comment char , use the above command
In regex, ^ indicates the beginning of a line, and $ the end of a line,
So ^$ specifies lines where the start of line character and the end of line character are right next to each other.