Hi, using a Perl CGI script, I am trying to manage a list of people and attributes about the people in a colon-delimited flat file and I am trying to generate a perl script that will add, change, and remove entries to this file. For example, the file might look like this: 
  John Smith:26:healthy:Linux
  Joe Jaz:21:cool:Irix
  ....

[download]
I can easily read the file and parse out the information. However, I am not sure how to remove an entry from the file. The way I see it, to remove an entry, I would have to read in the whole file into a variable or array, remove the content that I don't want and then write over the original file. However, would this process cause any problems if multiple people were writing or removing entries to that file at the same time or if the CGI script were interrupted before it finished processing? How might I ensure that my original data remains uncorrupted even with multiple users? If anyone has any thoughs on this subject, I would be very greatful. Thank you very much for reading this. Joe

In reply to How to modify/delete records in a flat-file database? by JoeJaz

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