How to tell if vim is being run in command line vs. powershell

Question

I would like to make a function which does the following

if (vim is running in powershell)
    call system("only works in powershell")
else
    echo "Skipping powershell command"

Does anyone know how to tell what program vim is being run from?

EDIT: echo &term outputs "win32" in both cases.

Answer 1

From what I see you don't need to check what vim was run from. You need to check the value of &shell because vim will run command in powershell if &shell option tells it to run command in powershell. If name of the shell is posh then checking may be done with

if stridx(&shell, 'posh')!=-1
    call system('only works in powershell')
else
    echo 'Skipping powershell command'
endif

. But I would rather suggest to run powershell directly with something like

call system('posh -c '.shellescape('only works in powershell'))

(note: I am not sure about what 'posh -c ' string should actually look like) or temporary set &shell option:

let savedsh=[&shell, &shellcmdflag, &shellxquote, &shellxescape, &shellquote, &shellpipe, &shellredir]
set shell=posh shellcmdflag=-c shellxquote=\" shellquote=\" shellpipe=> shellredir=>
try
    call system('only works in powershell')
finally
    let [&shell, &shellcmdflag, &shellxquote, &shellxescape, &shellquote, &shellpipe, &shellredir]=savedsh
endtry

(again, not sure about exact values of options): these ways command will always run in powershell.

Answer 2

You can check $term . For example on my cygwin and git bash , I get $term as cygwin .

For Powershell, you may set in your profile the following and check against that:

$env:TERM = "posh"

Note that &shell will cmd.exe for both cmd and powershell.