I want to check if a certain environment variable is set in the PC. If yes do x if not do y.
I tried these and some variations of them:
IF EXISTS %SIGN% runtest.exe --redirect -l %NAME%
ELSE runtest.exe -l %NAME%
if "%SIGN%" == "" runtest.exe --redirect -l %NAME%
ELSE runtest.exe -l %NAME%
None of them work well in both cases (when the environment variable SIGN exists and when it doesn't exist). Sometimes just in one case...
Please can you help? Thanks!
IF Conditionally perform a command
IF DEFINED SIGN (
runtest.exe --redirect -l %NAME%
) ELSE (
runtest.exe -l %NAME%
)
or shortly
IF DEFINED SIGN (runtest.exe --redirect -l %NAME%) ELSE (runtest.exe -l %NAME%)
Valid syntax:
), ELSE and ( must be on an only line as follows: ) ELSE (Note:
if DEFINEDwill return true if the variable contains any value (even if the value is just a space).
According to above predicate, IF DEFINED SIGN condition seems to be equivalent to reformulated test if NOT "%SIGN%"=="" but it is valid in batch only, where %undefined_variable% results to an empty string:
if NOT "%SIGN%"=="" (runtest.exe --redirect -l %NAME%) ELSE (runtest.exe -l %NAME%)
Otherwise, in pure CLI, %undefined_variable% results to %undefined_variable%
Proof:
==>type uv.bat
@echo undefined_variable="%undefined_variable%"
==>uv.bat
undefined_variable=""
==>echo undefined_variable="%undefined_variable%"
undefined_variable="%undefined_variable%"
==>
if exists checks for files.
For variables do: if defined sign (without the percent-signs)
if existschecks for files. for variables do:if defined sign(without the percent-signs