From: MEA-MikeFriedrichs <mfr...@ma...> - 2004-01-13 21:21:16
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Hello, I just downloaded MSYS, release 1.0.9 onto my WIN2k machine. I am building some HC12 code and it has been recommended to use MSYS to interface with the tools. In directory f:/msys. The startup batch file(msys.bat) has some commands I don't understand. Excerpt are as follows: rem Revision: 2.0 rem Revision Date: April 17th, 2002 if "x%COMSPEC%" == "x" set COMSPEC=command.com start %COMSPEC% /e:4096 /c %0 GOTO: _Resume %0 %1 %2 %3 %4 %5 %6 %7 %8 %9 goto EOF What does the 'x' imply that prefixes the environmental variable? Mike Friedrichs Machine Element Analysis 15865 Hwy 105 West; Ste.5 Montgomery, Texas 77356 ph: 936.588.3834 fax: 800.210.9586 |
From: Greg C. <chi...@mi...> - 2004-01-13 21:39:13
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MEA-MikeFriedrichs wrote: > > if "x%COMSPEC%" == "x" set COMSPEC=command.com > start %COMSPEC% /e:4096 /c %0 GOTO: _Resume %0 %1 %2 %3 %4 %5 %6 %7 %8 %9 > goto EOF > > What does the 'x' imply that prefixes the environmental variable? Standard batch-file workaround. You can't directly compare to an empty string. Or at least you couldn't the last time I worked with batch files. |
From: MEA-MikeFriedrichs <mfr...@ma...> - 2004-01-14 00:49:26
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Thanks, that's pretty obvious now, I didn't notice that on the first pass. MikeF At 03:39 PM 01/13/2004, you wrote: >MEA-MikeFriedrichs wrote: > > > > if "x%COMSPEC%" == "x" set COMSPEC=command.com > > start %COMSPEC% /e:4096 /c %0 GOTO: _Resume %0 %1 %2 %3 %4 %5 %6 %7 %8 %9 > > goto EOF > > > > What does the 'x' imply that prefixes the environmental variable? > >Standard batch-file workaround. You can't directly compare to an >empty string. Or at least you couldn't the last time I worked >with batch files. |