pid=$(ps -l -p $pid | grep -v PPID | perl -ane 'print $F[4]')

##</code><code>##

ppidi=4
[ $(uname) = 'Cygwin ] && ppidi=1

...

 pid=$(ps -l -p $pid | grep -v PPID | \
perl -ane 'print $F[$ARGV[0]]' $ppidi); 

##</code><code>##

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