How to clear log files

PostgreSql:8.4.1

Is there a way for me to tell postgres to clear the log file.  Example:  I have log files created with names corresponding to the days of the week.  This way they overwrite each other every week.  When I deploy software enhancements I would like to clear the log file for the day without having to stop postgres.  This way anything I see I know was after the deployment of my enhancements.  I tried to just delete the file with postgres running.  I found that it did not recreate the log file so I was forced to restart postgres.

Is there a command that might clear a log file or force it to rotate?

Thanks,

Lance Campbell

Software Architect/DBA/Project Manager

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