Melodius Monks,

Did I just mess up a file processing run?

I have a 1,000,000 line text file to process. The important part of the code is: 

open(FILE, $data_file) or die("cannot open file : $data_file $!");
print "<p>opened file $data_file ok\n";
    
while ($line = <FILE>) {
        
    DO A BUNCH OF STUFF WITH THIS LINE

}
close(FILE);

[download]

I start the program via telnet, and use NOHUP so it runs to the end. (NOHUP perl myscript.pl) The "print" statement gets printed out to a nohup.out file, an in my WHILE lopp there's a print statement that outputs the line number it's workig on every 1,000 lines so I know where it is.

Because there are about 1,000 operations to do on each line, it takes a looooooong time to run. It's running on a UNIX server.

In the middle of a run, someone deleted the data_file from the server by ftp.

I thought that using this form of while ($line = <FILE>) read in one line ata time from disk, and that deleting the file during arun would kill the running process, since it could no longer read from it. BUT - I see that my nohup.out file continues to be updated with lines being process. AND "ps U myusername" via telnet says myscript.pl is still running.

Is it possible that it really is still running? Have I misunderstood how ths works? Did it really read a copy of the file into cache or something that allows it to coninue with the file deleted?

Is there hope for me (or am I hopeless?)

Thanks.




Forget that fear of gravity,
Get a little savagery in your life.

In reply to What if FILE deleted during WHILE read-in loop? by punch_card_don

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