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BASH: Waiting for a process to end, problem with wait

Hi there folks, i came along with yet another issue with the wait command in BASH

The thing is i used BASH to run another script which is not mine, several times in a for loop. But i need to open the log files after each time the script that modifies some text file is done. I tried with wait and using the PID, but it says something like the process is not spawned from that console/terminal, so i recurred to a more dumb approach:

Code:

#        Wait till current file is gone

function espera 

{

sleep 3

current= path/$1.$2.string.current; # This is the temp file, deleted after the main script finishes

while [ -e $current ]

do

let i=1 # Dumb operation to keep the while loop running

done

sleep 1

busca $1 $2

prometeo $1 $2

}

busca() is for looking the actual log file and opening it; whilst prometeo(), logs the new data into a database

If you are going to use a busy loop to wait for a non-child process, at least put a delay time in the loop, otherwise you will be wasting CPU cycles (and electricity). For example, the following bash code will busy-wait for a process to finish:

Code:

while [ -e /proc/$PID ]; do sleep 0.1; done

If you want a dummy command, : is provide for exactly that purpose

Code:

c@CW8:~$ help :

:: :

    No effect; the command does nothing.  A zero exit code is returned.