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POHow to pause bash script from python script?
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copied!<p>I want to pause bash script from python script, the steps look like this: </p> <ol> <li><p>I start script writer.sh from python script reader.py.</p></li> <li><p>When writer.sh outputs third line I want executing of this script to be paused using some command in <code>reader.py</code>.</p></li> <li><p>I want to resume execution of writer.sh using some command in <code>reader.py</code>.</p></li> </ol> <p>Here are those two scripts, the problem is that <code>writer.sh</code> doesn't pause when sleep command is executed in <code>reader.py</code>. So my question is, how can I pause <code>writer.sh</code> when it outputs string "third"? To be exact (this is my practical problem in my job) I want <code>writer.sh</code> to stop because <code>reader.py</code> stopped reading output of <code>writer.sh</code>.</p> <p><code>reader.py</code>:</p> <pre><code>import subprocess from time import sleep print 'One line at a time:' proc = subprocess.Popen('./writer.sh', shell=False, stdout=subprocess.PIPE, ) try: for i in range(4): output = proc.stdout.readline() print output.rstrip() if i == 2: print "sleeping" sleep(200000000000000) except KeyboardInterrupt: remainder = proc.communicate()[0] print "remainder:" print remainder </code></pre> <p><code>writer.sh</code>:</p> <pre><code>#!/bin/sh echo first; echo second; echo third; echo fourth; echo fith; touch end_file; </code></pre> <p>Related question is, will using pipes on Linux pause script1, if script1 outputs lines of text, e.g. <code>script1 | script2</code>, and script2 pauses after reading third line of input?</p>

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