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copied!<p>Try this instead:</p> <pre><code>ps aux | grep -q "[p]rocessName" if [ $? -eq 0 ]; then echo "running" else echo "not running" fi </code></pre> <p>The brackets around the first letter of processName means do don't need the "grep -v grep", while the -q means we don't need the pipe to /dev/null</p> <p>$? gives you the return code of the previous command executed. Hence, testing if it were 0 would indicate if "grep" found what it was looking for.</p> <p><strong>Update</strong></p> <p>If your process name is really short (say "cup"), you might get a false positive as it may match other processes too (say "cupsd"). You can overcome this by having grep match whole words - add the "-w" flag.</p> <p>Not that this technique is not perfect. You may end up matching entries in the username/date fields. If that happens, look up "man ps" and be more selective of what you print out before doing a grep. Alternatively, prefilter the output with awk to extract only the column showing process/cmd name . E.g:</p> <pre><code>ps aux | awk '{print $11}' | grep -q -w "[p]rocessName" if [ $? -eq 0 ]; then echo "running" else echo "not running" fi </code></pre> <p><strong>Update 2</strong></p> <p>you can also use pgrep as suggested in answer below. </p> <p>For really short process names, you might want to specify word boundaries (\b) before and after your process name to prevent overmatching (as described above)</p> <pre><code>pgrep "\bprocname\b" > /dev/null if [ $? -eq 0 ]; then echo "running" else echo "not running" fi </code></pre> <p><strong>Update 3</strong></p> <p>From the updated question, I see that you're running it from an init script. There's always a danger of pgrep matching the script itself. Try:</p> <pre><code>pgrep Processname | grep -q -v $$ if [ $? -eq 0 ]; then echo "running" else echo "not running" fi </code></pre> <p>That excludes the PID of the script from pgrep matches.</p> <p><strong>Update 4</strong></p> <p>(final update? fingers crossed)</p> <p>If the init script is run via the "service" command, then we need to filter out the parent PID as well. How about:</p> <pre><code>pgrep Processname | grep -v $$ | grep -q -v $PPID if [ $? -eq 0 ]; then echo "running" else echo "not running" fi </code></pre>

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