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## pgrep example ##
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pgrep -x mysqld >/dev/null && echo "Process found" || echo "Process not found"
pgrep -x httpd >/dev/null && echo "Process found" || echo "Process not found"
 
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## pidof example ##
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pidof httpd >/dev/null && echo "Service is running" || echo "Service NOT running"
pidof nginx >/dev/null && echo "Service is running" || echo "Service NOT running"
 
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## ps example ##
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ps -C httpd >/dev/null && echo "Running" || echo "Not running"
ps -C nginx >/dev/null && echo "Running" || echo "Not running"