<a href="http://www.solarum weight reduction pills.com/wp-content/uploads/2012/08/ken-and-den-1024.jpg” target=”_blank”>If you spend any amount of time working with or administering UNIX and/or Linux servers, especially UNIX, you should be familiar with the text editor ‘vi’ and some commands like ‘sed’ and ‘awk’. If you have been around a while, or had the good(?) fortune of working on some old(er) systems, you might even remember the line editor ‘ed’. I’ll show my age here and recall fond memories of using ‘ed’ to write code many years back.
OK, on to the point, I was looking through Wikipedia for something entirely un-related, but ran across a tidbit of information that I thought was really cool, and that I knew I had to share with Solarum’s readers. It gives a bit of history about some of the tools that we use and love today.
“ed is a line editor for the Unix operating system. It was one of the first end-user programs hosted on the system and has been standard in Unix-based systems ever since. ed was originally written in PDP-11/20 assembler by Ken Thompson in 1971. Ken Thompson was very familiar with an earlier editor known as qed from University of California at Berkeley, Ken Thompson’s alma mater; he reimplemented qed on the CTSS and Multics systems, so it is natural that he carried many features of qed forward into ed. Ken Thompson’s versions of qed were the first to implement regular expressions, an idea that had previously been formalized in a mathematical paper, which Ken Thompson had read. The implementation of regular expressions in ed is considerably less general than the implementation in qed.
ed went on to influence ex, which in turn spawned vi. The non-interactive Unix command grep was inspired by a common special use of qed and later ed, where the command g/re/p means globally search for the regular expression re and print the lines containing it. The Unix stream editor, sed implemented many of the scripting features of qed that were not supported by ed on Unix; sed, in turn, influenced the design of the programming language AWK, which in turn inspired aspects of Perl.”
It’s pretty cool how stuff flows and comes together. Who knew or would have thought that a couple simple commands or programs would turn into what we have today.
*Note: starnix refers to the combination of UNIX, Linux and any other ix/ux OS that we work with.