ERRORLEVEL and Where.exe program

[BoQsc]

I'd like to have a readable form of code that checks whether a program is available to be used.

It's mostly to check if the program is available from the PATH Environment Variable.


I'd like to ask if this makes any sense and is a correct way to do that, or you have any improvements on that.

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@ECHO OFF
WHERE cmd.exe
IF ERRORLEVEL 01 ECHO the program is not found.
PAUSE

NOTES:
/Q argument can be added to silent the output of Where.exe program.

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WHERE /Q cmd.exe

Also the alternative:

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WHERE cmd.exe >NUL 2>NUL

Update
The same above maybe can be rewritten as this:

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@ECHO OFF
WHERE cmd.exe || ECHO the program is not found.
PAUSE

A shorter version indeed, but maybe not much of a pleasure to read.

[T3RRY]

My preferred solution is to define the programs name to a variable like so:

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 For /F "Delims=" %%G in (' where programname.ext 2^> Nul ')Do Set "%%~nG=%%G"

And then to execute you can make it conditional on the variables definition.

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 If defined programname (
  rem commands to execute
 )
 

[jfl]

It's also possible to do that without invoking the where.exe program at all. Ex:

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C:\JFL\Temp>for %p in (notepad.exe) do @echo set N=%~$PATH:p
set N=C:\Windows\System32\notepad.exe

C:\JFL\Temp>for %p in (nothing.exe) do @echo set N=%~$PATH:p
set N=

C:\JFL\Temp>

In a batch file, it'd become:

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for %%p in (programname.ext) do set %%~np=%%~$PATH:p
if defined programname echo Yes it exists: %programname%

Actually there is a difference to be aware of:
where.exe will find the program _without_ having to specify the extension, whereas the for ... %~$PATH syntax requires the exact extension.
Ex: 'where notepad' finds notepad.exe, and also a script called notepad.bat if you have one in your PATH.