Assign output of a program to a variable using a MS batch file

Question

I need to assign the output of a program to a variable using a MS batch file   So in GNU Bash shell I would use VAR   application arg0 arg1   I need a similar behavior in Windows using a batch file   Something like set VAR application arg0 arg1

User · Answer

Some macros to set the output of a command to a variable/

For directly in the command prompt

c:\>doskey assign=for /f "tokens=1,2 delims=," %a in ("$*") do @for /f "tokens=* delims=" %# in ('"%a"') do @set "%b=%#"

c:\>assign WHOAMI /LOGONID,my-id

c:\>echo %my-id%

Macro with arguments

As this macro accepts arguments as a function i think it is the neatest macro to be used in a batch file:

@echo off

::::: ---- defining the assign macro ---- ::::::::
setlocal DisableDelayedExpansion
(set LF=^
%=EMPTY=%
)
set ^"\n=^^^%LF%%LF%^%LF%%LF%^^"

::set argv=Empty
set assign=for /L %%n in (1 1 2) do ( %\n%
   if %%n==2 (%\n%
      setlocal enableDelayedExpansion%\n%
      for /F "tokens=1,2 delims=," %%A in ("!argv!") do (%\n%
         for /f "tokens=* delims=" %%# in ('%%~A') do endlocal^&set "%%~B=%%#" %\n%
      ) %\n%
   ) %\n%
) ^& set argv=,

::::: -------- ::::::::


:::EXAMPLE
%assign% "WHOAMI /LOGONID",result
echo %result%

FOR /F macro

not so easy to read as the previous macro.

::::::::::::::::::::::::::::::::::::::::::::::::::
;;set "{{=for /f "tokens=* delims=" %%# in ('" &::
;;set "--=') do @set ""                        &::
;;set "}}==%%#""                               &::
::::::::::::::::::::::::::::::::::::::::::::::::::

:: --examples

::assigning ver output to %win-ver% variable
%{{% ver %--%win-ver%}}%
echo 3: %win-ver%


::assigning hostname output to %my-host% variable
%{{% hostname %--%my-host%}}%
echo 4: %my-host%

Macro using a temp file

Easier to read , it is not so slow if you have a SSD drive but still it creates a temp file.

@echo off

:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
;;set "[[=>"#" 2>&1&set/p "&set "]]==<# & del /q # >nul 2>&1" &::
:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

chcp %[[%code-page%]]%
echo ~~%code-page%~~

whoami %[[%its-me%]]%
echo ##%its-me%##

User · Answer

In addition to the answer  you can t directly use output redirection operators in the set part of for loop  e g  if you wanna hide stderror output from a user and provide a nicer error message   Instead  you have to escape them with a caret character       for  f   O in   some-erroring-command 2  gt  nul   do  echo   O    Reference  Redirect output of command in for loop of batch script

User · Answer

As an addition to this previous answer  pipes can be used inside a for statement  escaped by a caret symbol       for  f  tokens      i in   tasklist    grep  explorer    do set VAR   i

User · Answer

On Executing  for  f   i in   application arg0 arg1   do set VAR   i i was getting error    i was unexpected at this time   As a fix  i had to execute above as for  f  i in   application arg0 arg1   do set VAR  i

User · Answer

OP  you can use for loops to capture the return status of your program  if it outputs something other than numbers

User · Answer

echo off SETLOCAL ENABLEDELAYEDEXPANSION  REM Prefer backtick usage for command output reading  REM ENABLEDELAYEDEXPANSION is required for actualized REM  outer variables within for s scope  REM within for s scope  access to modified  REM outer variable is done via       syntax   SET CHP C  Windows System32 chcp com  FOR  F  usebackq tokens 1 2 3    i IN    CHP    DO       IF    i      Aktive  IF    j      Codepage             SET SELCP   k         SET SELCP  SELCP  0 -1          echo actual codepage   SELCP    ENDLOCAL

User · Answer

You could use a batch macro for simple capturing of command outputs  a bit like the behaviour of the bash shell  The usage of the macro is simple and looks like   set  VAR application arg1 arg2  And it works even with pipes   set  allDrives  quot wmic logicaldisk get name  value   findstr  quot Name quot  quot   The macro uses the variable like an array and stores each line in a separate index  In the sample of   set  allDrives  quot wmic logicaldisk there will the following variables created  allDrives Len 5 allDrives Max 4 allDrives 0  Name C  allDrives 1  Name D  allDrives 2  Name F  allDrives 3  Name G  allDrives 4  Name Z  allDrives  lt contains the complete text with line feeds gt   To use it  it s not important to understand how the macro itself works  The full example  echo off setlocal  call  initMacro    set  ipOutput  quot ipconfig quot  call  ShowVariable ipOutput echo First line is  ipOutput 0    echo     set  driveNames  quot wmic logicaldisk get name  value   findstr  quot Name quot  quot  call  ShowVariable driveNames  exit  b   ShowVariable setlocal EnableDelayedExpansion for  L   n in  0 1    1 max   do       echo   n     1   n     echo  exit  b   initMacro if  quot    quot    quot  quot        echo ERROR  Delayed Expansion must be disabled while defining macros      goto  2 gt nul      goto  2 gt nul    set LF     empty      set  n       empty      set  set FOR  L   N in  1 1 2  dO IF   N  2     n      setlocal EnableDelayedExpansion                                   n      for  f  quot tokens 1   delims    quot    1 in   quot  argv  quot   do                n          endlocal                                                      n          endlocal                                                      n          set  quot    1 Len 0 quot                                               n          set  quot    1  quot                                                    n          if  quot    quot    quot  quot                                                    n                 Used if delayed expansion is enabled                   n                  setlocal DisableDelayedExpansion                      n                  for  F  quot delims  quot    O in    quot    2   findstr  N    quot    do     n                  if  quot    quot  NEQ  quot  quot                                         n                      endlocal                                          n                                                                        n                  setlocal DisableDelayedExpansion                      n                  set  quot line   O quot                                         n                  setlocal EnableDelayedExpansion                       n                  set pathExt                                           n                  set path                                              n                  set  quot line  line       quot                                 n                  set  quot line  line  quot  q quot   quot  quot   quot                              n                  call set  quot line   line    q quot  quot      quot                      n                  set  quot line  line q quot  quot     quot                                n                  set  quot line  quot  line      quot  quot                                n                  for  F   C in   quot     1 Len  quot   do                       n                      FOR  F  quot delims  quot    L in   quot  line  quot   Do             n                          endlocal                                      n                          endlocal                                      n                          set  quot    1   C     L quot                           n                          if   C    0                                   n                              set  quot    1    L quot                            n                            ELSE                                        n                              set  quot    1     1  LF    L quot                  n                                                                        n                                                                        n                      set  a    1 Len  1                                n                                                                        n                                                                        n            ELSE                                                        n                 Used if delayed expansion is disabled                  n              for  F  quot delims  quot    O in    quot    2   findstr  N    quot    do     n                  setlocal DisableDelayedExpansion                      n                  set  quot line   O quot                                         n                  setlocal EnableDelayedExpansion                       n                  set  quot line  quot  line      quot  quot                                n                  for  F   C in   quot     1 Len  quot   DO                       n                      FOR  F  quot delims  quot    L in   quot  line  quot   DO             n                          endlocal                                      n                          endlocal                                      n                          set  quot    1   C     L quot                           n                                                                        n                      set  a    1 Len  1                                n                                                                        n                                                                        n                                                                        n          set  a    1 Max    1 Len-1                                    n                                                                        n        else setlocal DisableDelayedExpansion  amp set argv   goto  eof

User · Answer

One way is   application arg0 arg1  gt  temp txt set  p VAR  lt temp txt   Another is   for  f   i in   application arg0 arg1   do set VAR   i   Note that the first   in   i is used to escape the   after it and is needed when using the above code in a batch file rather than on the command line  Imagine  your test bat has something like   for  f   i in   c  cygwin64 bin date exe     Y  m  d  H  M  S    do set datetime   i echo  datetime

User · Answer

I wrote the script that pings google com every 5 seconds and logging results with current time  Here you can find output to variables  commandLineStr   with indices    echo off   LOOPSTART  echo  DATE  0   TIME  0 8   gt  gt  Pingtest log  SETLOCAL ENABLEDELAYEDEXPANSION SET scriptCount 1 FOR  F  tokens   USEBACKQ    F IN   ping google com -n 1   DO     SET commandLineStr scriptCount    F   SET  a scriptCount  scriptCount  1    ECHO  commandLineStr1   gt  gt  PingTest log  ECHO  commandLineStr2   gt  gt  PingTest log ENDLOCAL  timeout 5  gt  nul  GOTO LOOPSTART

User · Answer

assuming that your application s output is a numeric return code  you can do the following  application arg0 arg1 set VAR  errorlevel

[batch-file] Assign output of a program to a variable using a MS batch file

For directly in the command prompt

Macro with arguments

FOR /F macro

Macro using a temp file

Examples related to batch-file

Examples related to cmd

Examples related to variable-assignment

Examples related to windows-console