Haha, wow... I'm sorry I seemed to have sparked quite the discussion :-p I certainly appreciate all the help!

I am indeed an uber noob, and I have actually zero experience with awk. Although it seems to make sense to separate the data into "|" delimited fields, the sed command seems much simpler and easier for me to read (even though it is still a bit cryptic.... regex is seriously the bane of my existence). Plus, the case previously mentioned in which I might have more than one tcolor field, for example, would not be an issue.

That being said... unfortunately, doing the following:

Code:

grep "title=Boston" datafile | sed 's/tcolor=[^|]*/tcolor=blue/'

...does not seem to change the info in the datafile itself.


See, I have an html form that allows the user to enter in these fields into text boxes.. then they are added to the datafile via a .cgi script. If the user goes back and enters in new info for a data item who's title already exists in the datafile, then the new values are meant to replace the old.

So, if the datafile is as follows:

Code:

title=Boston|tcolor=green|desc=Large city in New England|url=http://www.boston.com
title=New York|tcolor=gold|desc=The largest city on the East Coast|url=http://www.newyork.com
title=Dallas|tcolor=silver|desc=A sprawling, cheery Texas city|url=http://www.dallas.com

and the .cgi script passes in the following parameters in the query string:

Code:

title=Boston&titlecolor=blue&descrip=&url=

Once the query string is parsed, what would be the best way to go about testing which parameter is not an empty string, and only updating that field (in this case the tcolor field in the $title line with $titlecolor) in the datafile?


...I hope that all makes sense, haha. Again, thank you for the help!