From: "Buchbinder, Barry (NIH/NIAID) [E]" <BBuchbinder@niaid.nih.gov>
To: "cygwin@cygwin.com" <cygwin@cygwin.com>
Date: Sun, 10 Jun 2012 13:41:25 -0400
Subject: RE: Shell script loop runs out of memory
Message-ID: <0105D5C1E0353146B1B222348B0411A20A770AB442@NIHMLBX02.nih.gov>
References: <loom.20120531T193933-322@post.gmane.org> <CANs8wdBYOBGsmp2iFSSOOd5FZ4qb3i3a-E2EM8LBbPKz=su5Pg@mail.gmail.com> <786EBDA1AC46254B813E200779E7AD36023A42C2@srv1163ex1.flightsafety.com> <loom.20120531T211830-607@post.gmane.org> <0105D5C1E0353146B1B222348B0411A20A770C827D@NIHMLBX02.nih.gov>
In-Reply-To: <0105D5C1E0353146B1B222348B0411A20A770C827D@NIHMLBX02.nih.gov>
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Just to complete this topic ...

This gets rid of all the fork-execs in the inner loop except
for sleep.  Instead of comparing file contents, it uses
the test builtin to compare time stamps.

------------------------
#!/bin/dash

FILE_TO_CHECK=/mypath/style.less
COMPARE_FILE=/mypath/compare_file.tmp
echo -n > $COMPARE_FILE

while [ 1 = 1 ]
do
	echo "Waiting for file to change..."
	while [ 1 = 1 ]
	do
		if [ $FILE_TO_CHECK -nt $COMPARE_FILE ]
		then
			break
		fi
		sleep 1
	done
	echo -n > ${COMPARE_FILE}
	echo "File was modified ... Running compiler..."
	/mypath/lessc $FILE_TO_CHECK /mypath/style.css -x
done
------------------------

A question I have is whether using a DOS version of sleep would
avoid the consumption of resources.  In other words, is the
problem caused by the fork-exec or launching a new cygwin
process.  If the latter, might that be avoid by use of a DOS
version of sleep?  (I have one if the OP wants to try it.)

I apologize for taking so long to post this.

- Barry
  Disclaimer:  Statements made herein are not made on behalf of NIAID.

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