What does ' @(#)cshrc 1.11 89/11/29 SMI ' mean?
Can someone please deconstruct and explain the parts?
# @(#)cshrc 1.11 89/11/29 SMI
It is at the top of a the .cshrc of a new Solaris account I am working on.
I am familiar with using the first line of a script for setting the program/shell to use. Example: #!/bin/csh or #!/bin/sh or #!/ben/perl.
I am also familiar with leaving the first line blank or adding a comment. For .cshrc (opposed to my_script.csh) I just start with a # comment line.
Searching the internets, I see lots of examples of .cshrc posted that begin with this line, but I have not found anybody who explains what it is doing or where it comes from. The best I tell, it is just a comment. But why does it appear at the beginning of so many .cshrc files?
This is a standard header found in many shell scripts/config files in Solaris.
1.11 is a version of the file I think. 89/11/29 is a date (1989-11-29). SMI is an acronym for Sun MIcrosystems.
It looks like bartus11 has mostly answered your question. It is an sccs (Source Code Control System) ID comment. In this case it says that this script is version 1.11 and was last updated on November 29, 1989. The SMI is for Sun Microsystems, Inc.
Once upon a time, every file that was part of a Solaris system distribution that had a place where a comment could be included contained a line like this. Binary files also contained data like this. You can use the what utility to extract this information from any file that contained the @(#) sccs ID introducer.