Hi, I'm Stephen Nicholas.

And this is my blog. I'm a software engineer by trade (but mostly for fun) with a wide variety of experience and interests. Some of which I'll write about here.

Finding processes on (i.e. ps for) Windows

As part of creating some test infrastructure for a work project the other day, I was looking for a good way to find any existing / leftover processes, so I could ensure things were in a clean state at the start of each test run. On Linux this is pretty easy, using ps, but I couldn’t find a good way to do it on Windows.

There’s the tasklist command, which will output the following:


Image Name                     PID Session Name        Session#    Mem Usage
========================= ======== ================ =========== ============
System Idle Process              0 Services                   0         24 K
System                           4 Services                   0      1,996 K
smss.exe                       448 Services                   0      1,380 K

And for most cases, that’s enough. But I was looking for a particular Java process and unfortunately I couldn’t tell which of the java.exe processes were the ones I was interested in and which were for something else – as tasklist doesn’t provide enough information (i.e. the launch parameters).

After a fair bit of Googling (which I’m hoping to save someone), I came accross a pretty cool command line interface called WMIC (Intro & Examples) that’s immensely powerful for gathering information from Windows-based systems (and is installed by default since Windows 2000).

It seems to do a whole load of stuff, but I was particularly interested in the process side of things and found that I could simply do:

C:\Users\IBM_ADMIN>WMIC PROCESS GET Caption,Processid,Commandline

Caption		CommandLine		ProcessId
java.exe 	java -Xmx128m -cp ".\lib;.\liblib\GAIANDB.jar;.\liblib\db2jcutdown.jar;.\liblib\derbyclient.jar;.\liblib\derby.jar;.\liblib\derbynet.jar;.\liblib\derbytrimmed.jar;.\liblib\wpml-pfg.jar;.\liblib\siapi.jar;.\liblib\esapi.jar;.\liblib\wmqtt.jar;C:\APPS\wpml-1.2\lib\wpml.jar;C:\APPS\wpml-1.2\lib\JSON4J.jar;C:\APPS\wpml-1.2\lib\arenatk.jar;C:\APPS\wpml-1.2\lib\antlr-2.7.7.jar;.\liblib\db2jcc.jar;.\liblib\db2jcc_license_cu.jar;.\liblib\ojdbc14.jar;.;C:\PROGRA~1\IBM\SQLLIB\java\db2java.zip;C:\PROGRA~1\IBM\SQLLIB\java\db2jcc.jar;C:\PROGRA~1\IBM\SQLLIB\java\sqlj.zip;C:\PROGRA~1\IBM\SQLLIB\java\db2jcc_license_cu.jar;C:\PROGRA~1\IBM\SQLLIB\bin;C:\PROGRA~1\IBM\SQLLIB\java\common.jar"  com.ibm.gaiandb.GaianNode 	7840

Now, this spits out info for all running processes (I’ve greatly trimmed down the result above), but I then found you can also pass in WHERE commands to restrict things to exactly what you want. E.g.

C:\Users\IBM_ADMIN>WMIC PROCESS WHERE (CommandLine like '%com.ibm.gaiandb.GaianNode%' AND name='java.exe') GET processid


Which I could then easily parse to get the info I wanted.

Note: In the above examples, I’ve restricted the fields that are returned. If you don’t restrict the GET, the full list of things that is returned is:

Caption, CommandLine, CreationClassName, CreationDate, CSCreationClassName, CSName, Description, ExecutablePath, ExecutionState, Handle, HandleCount, InstallDate, KernelModeTime, MaximumWorkingSetSize, MinimumWorkingSetSize, Name, OSCreationClassName, OSName, OtherOperationCount, OtherTransferCount, PageFaults, PageFileUsage, ParentProcessId, PeakPageFileUsage, PeakVirtualSize, PeakWorkingSetSize, Priority, PrivatePageCount, ProcessId, QuotaNonPagedPoolUsage, QuotaPagedPoolUsage, QuotaPeakNonPagedPoolUsage, QuotaPeakPagedPoolUsage, ReadOperationCount, ReadTransferCount, SessionId, Status, TerminationDate, ThreadCount, UserModeTime, VirtualSize, WindowsVersion, WorkingSetSize WriteOperationCount, WriteTransferCount