Difference between $? and $LastExitCode in PowerShell
WindowsPowershellCommand LineWindows Problem Overview
In PowerShell, what is the difference between $?
and $LastExitCode
?
I read about automatic variables, and it said:
> $? Contains the execution status of the last operation. It contains TRUE if the last operation succeeded and FALSE if it failed.
>
> $LastExitCode Contains the exit code of the last Windows-based program that was run.
In the definition of $?
it doesn't explain what succeed and fail mean.
I ask because I presumed that $?
is True if and only if $LastExitCode is 0, but I found a surprising counter-example: $LastExitCode=0 but $?=False in PowerShell. Redirecting stderr to stdout gives NativeCommandError.
Windows Solutions
Solution 1 - Windows
$LastExitCode
is the return code of native applications. $?
just returns True
or False
depending on whether the last command (cmdlet or native) exited without error or not.
For cmdlets failure usually means an exception, for native applications it's a non-zero exit code:
PS> cmd /c "exit 5"
PS> $?
False
PS> cmd /c "exit 0"
PS> $?
True
Cancelling a cmdlet with Ctrl+C will also count as failure; for native applications it depends on what exit code they set.