I'm generating output from a grep command, which I then want to process in grep again, filtering out my unwanted text. In this specific example, I want to filter out all lines that start with zero or more white space, followed by the comment characters "//". Here is what I thought I would use:
grep StopProductServices *.rul *.h | grep ^\s*[^/] The first grep obviously finds all occurrences of StopProductServices within all *.rul and *.h files. Then that output is piped into grep, with the intent being to start at the beginning of the line (the caret), allow any amount of white space (zero or more), and then match only if the first non-white space charater is NOT a forward slash. What it appears to be doing is to match the exact opposite of what I want. To break it down a little, I first produced the output from the first grep, which is used for the pipe: ->grep StopProductServices *.rul *.h NTService.rul:// FUNCTION: StopProductServices(sProduct) NTService.rul:// 03/24/08 MSF - Make StopProductServices() take an additional parameter to NTService.rul:function StopProductServices(sProduct) NTService.rul:// 03/24/08 MSF - Make StopProductServices() take an additional parameter to NTService.rul:// Function: SafeStopProductServices NTService.rul:// 03/24/08 MSF - Make StopProductServices(), SafeStopProductServices() and NTService.rul:function SafeStopProductServices(sProduct) NTService.rul: bServicesStopped = StopProductServices(sProduct); NTService.rul:// 03/24/08 MSF - Make StopProductServices(), SafeStopProductServices() and Setup.rul:// - Use Start... and StopProductServices() to stop VESTA and Setup.rul:// 03/31/08 MSF - Use Start... and StopProductServices() to stop VESTA and Setup.rul:// 03/31/08 MSF - Use Start... and StopProductServices() to stop VESTA and Setup.rul: StopProductServices(@PRODUCT_NAME); Setup.rul: StopProductServices(VESTA_VIEW); NTService.h:// 09/07/07 MSF - New functions StopProductServices(), NTService.h:// SafeStopProductServices() and DisableProductServices(). NTService.h:// 03/24/08 MSF - Make StopProductServices(), SafeStopProductServices() and NTService.h:prototype StopProductServices(STRING); NTService.h:prototype SafeStopProductServices(STRING); Then I ran the full command, and you can see that the output is not at all what I expected: [11:06:39]: *** C:\WIP\VESTA\Installer\Script Files *** ->grep StopProductServices *.rul *.h | grep ^\s*[^/] NTService.rul:// FUNCTION: StopProductServices(sProduct) NTService.rul:// 03/24/08 MSF - Make StopProductServices() take an additional parameter to NTService.rul:// 03/24/08 MSF - Make StopProductServices() take an additional parameter to NTService.rul:// Function: SafeStopProductServices NTService.rul:// 03/24/08 MSF - Make StopProductServices(), SafeStopProductServices() and NTService.rul:// 03/24/08 MSF - Make StopProductServices(), SafeStopProductServices() and Setup.rul:// - Use Start... and StopProductServices() to stop VESTA and Setup.rul:// 03/31/08 MSF - Use Start... and StopProductServices() to stop VESTA and Setup.rul:// 03/31/08 MSF - Use Start... and StopProductServices() to stop VESTA and NTService.h:// 09/07/07 MSF - New functions StopProductServices(), NTService.h:// SafeStopProductServices() and DisableProductServices(). NTService.h:// 03/24/08 MSF - Make StopProductServices(), SafeStopProductServices() and Here is what I thought I would get: NTService.rul:function StopProductServices(sProduct) NTService.rul:function SafeStopProductServices(sProduct) NTService.rul: bServicesStopped = StopProductServices(sProduct); Setup.rul: StopProductServices(@PRODUCT_NAME); Setup.rul: StopProductServices(VESTA_VIEW); NTService.h:prototype StopProductServices(STRING); NTService.h:prototype SafeStopProductServices(STRING);
