I find myself needing this command and unable to remember it or find it on Google easily. So I'm going to make a note of it here to save my precious memory for other more important information:
My Perl program wants to report it's SVN Id keyword. Setting this up is simple enough if you follow one of the many excellent examples on the web. However I found that it was beyond me to get the value of my Id printed out by my code.
The problem is that the completed SVN Id keyword contains @ and $ symbols.
So my code resorts to greping it's self to get the value from the source code.
# $Id$
my $id_str = `grep -m1 '\$Id:' $0`;
print $id_str;
It feels like a crime against programming, but it works - and provided that there is an $Id$ before the grep command, it should work reliabably.