check if program running in linux

Inshell,weusethebelowprogramtocheckifsomeprogramalreadyrunning:

exportHOMEDIR=/../../

exportJAVA_HOME=/usr/lib/jvm/java-1.6.0

exportLOGFILE=/tmp/log_`date+"%Y%m%d-%H%M%S"`.log

exportJAVA_CMD=$JAVA_HOME/bin/java

exportCLASSPATH=$JAVA_HOME/lib/tools.jar:$HOMEDIR/lib/ojdbc-14.jar:$HOMEDIR/lib/log4j-1.2.14.jar:$HOMEDIR/lib/commons-logging-1.1.jar

exportMAIN_PROGRAM=com.test.theClassEntry

ps-ef|grep"java">SomeFile

num=$(wc-lSomeFile|awk'{print$1}')

if[$num-gt0]

then

echo"thejavaprocessisrunning">$LOGFILE

exit1

else

nohup$JAVA_CMD-Xmx10g-Dflag=true-classpath"$CLASSPATH"$MAIN_PROGRAMprogram_parameter>$LOGFILE2>&1&

fi

note:

1.-Dproperty=value

Setasystempropertyvalue.Youcancallthefollowingfromanywhereinthecodetoreadthepropertiesgivenonthecommandline:

Stringvalue=System.getProperty("key","defaultvalue");

2.

http://www.linfo.org/ps.html

Analternativesetofoptionsforviewingalltheprocessesrunningonasystemis

ps-ef|less

The-eoptiongeneratesalistofinformationabouteveryprocesscurrentlyrunning.The-foptiongeneratesalistingthatcontainsfeweritemsofinformationforeachprocessthanthe-loption.

3.

http://www.thegeekstuff.com/2010/01/awk-introduction-tutorial-7-awk-print-examples/

AwkExamplePrintonlyspecificfield.

Awkhasnumberofbuiltinvariables.Foreachrecordi.eline,itsplitstherecorddelimitedbywhitespacecharacterbydefaultandstoresitinthe$nvariables.Ifthelinehas4words,itwillbestoredin$1,$2,$3and$4.$0representswholeline.NFisabuiltinvariablewhichrepresentstotalnumberoffieldsinarecord.

$awk'{print$2,$5;}'employee.txt

Thomas$5,000

Jason$5,500

Sanjay$7,000

Nisha$9,500

Randy$6,000

$awk'{print$2,$NF;}'employee.txt

Thomas$5,000

Jason$5,500

Sanjay$7,000

Nisha$9,500

Randy$6,000

Intheaboveexample$2and$5representsNameandSalaryrespectively.WecangettheSalaryusing$NFalso,where$NFrepresentslastfield.Intheprintstatement‘,’isaconcatenator.