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piping output of tail running in background

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# 1  
Old 07-26-2007
piping output of tail running in background
Not sure why this does not work in bash:
tail -f err.log |&
-bash: syntax error near unexpected token `&'

I am attempting to continuously read a file that is being updated by doing a "tail -f" on the file and piping the output to stdin which can then be read by the next shell command

Thnx
# 2  
Old 07-27-2007
Hi,
What's sort of next unix command do you want to apply on the continious tail ?
# 3  
Old 07-27-2007
What you are trying is co-processing and not piping.

piping would be something like this:

Code:
ls -l | pg

In the above example output of the ls -l command is piped to pg, which will display the output in page break ups.

refer to this thread
# 4  
Old 07-27-2007
piping output of tail running in background
Thanks for the replies. Excuse my using wrong terminology - yes i was attempting a coprocess by "tailing" a log file and have its stdout be read by a read in the current script - something like this...
Code:
tail -f $LOGFILE |&
while read -p line

I found my problem was with the shell that i was using. It does not work in the bash shell but does work in ksh.
# 5  
Old 07-27-2007
Code:
tail -f $LOGFILE | \
while read -p line
...

or
Code:
tail -f $LOGFILE | while read -p line
...

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