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Opening output file while still in process


 
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# 1  
Old 03-02-2006
Opening output file while still in process

Dear guru,

Say I have a long process that is executed in this way:

$ nohup perl mycode.pl > output.txt &

Now if I want to view the output file with vi, while process
still running:

$ vi output.txt

Will it kill the process? (seems to me it does). If so how can view the file
without having to kill it.

Thanks and hope to hear from you again.

Regards,
Edward
# 2  
Old 03-02-2006
Try

Code:
cat output.txt

Better yet,
Code:
tail -f output.txt

# 3  
Old 03-02-2006
Thanks. One more thing, how about copying file before opening it?

$cp outfile.txt newname.txt

$vi newname.txt

Will it kill the process?
# 4  
Old 03-02-2006
Quote:
Originally Posted by monkfan
Thanks. One more thing, how about copying file before opening it?

$cp outfile.txt newname.txt

$vi newname.txt

Will it kill the process?
No it will not kill the process

Gaurav
# 5  
Old 03-02-2006
the process that is dumping data to an output file will not be killed
untill the environment or the user is changing the permission bits of the file to which it is dumped, or file descriptor problem, invalidating file handler etc.

when we want to view the file where data is dumped the shell provides you with a different file handler without affecting the prime process that is dumping into the file. Hence there is no consistency problem as far as reading a file and taking a copy is concerned.
 

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