I have a logging problem that is driving me buggy. I have a CGI program that receives XML from a customer, processes it, enters some of the information in an Oracle database, and returns an XML document to the customer. Each step along the way is logged to a buffer and written all at once as the program ends. Her eis how I write to the log: 

  # open for append
  open FILE, ">>$g_db_logfile";

  # wait for lock
  flock (FILE,LOCK_EX);
  
  # once lock is granted seek to end, JIC
  seek (FILE,0,2);
  
  # print the string
  print FILE "$logstr\n";
  

  # unlock file
  flock (FILE,LOCK_UN);
  
  # close file
  close FILE;

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The problem is that when several processes are running the log may not be written for all of them. I know the orders are coming in -- I can see them in the DB -- but I don't always get the expected log entry. Any ideas what I am doing wrong?

This particuar program is running on Perl 5.6.0.

In reply to File Locking in CGI programs by enemyofthestate

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