Can you redirect the output of a command to a variable with pipes?
I haven't tried much as I haven't been able to think of anything to try, but I have tried one method (with two variations)...
For example:
echo Hello|set text=
Didn't work, neither did:
echo Hello | set text=
I know you can do it fairly easily with the FOR command, but I think it would look "nicer" with a pipe.
And if you're wondering, I don't have a specific reason I'm asking this other than I'm curious and I can't find the answer.
This question is related to
batch-file
In a batch file I usually create a file in the temp directory and append output from a program, then I call it with a variable-name to set that variable. Like this:
:: Create a set_var.cmd file containing: set %1=
set /p="set %%1="<nul>"%temp%\set_var.cmd"
:: Append output from a command
ipconfig | find "IPv4" >> "%temp%\set_var.cmd"
call "%temp%\set_var.cmd" IPAddress
echo %IPAddress%
You can set the output to a temporary file and the read the data from the file after that you can delete the temporary file.
echo %date%>temp.txt
set /p myVarDate= < temp.txt
echo Date is %myVarDate%
del temp.txt
In this variable myVarDate contains the output of command.
I find myself a tad amazed at the lack of what I consider the best answer to this question anywhere on the internet. I struggled for many years to find the answer. Many answers online come close, but none really answer it. The real answer is
(cmd & echo.) >2 & (set /p =)<2
The "secret sauce" being the "closely guarded coveted secret" that "echo." sends a CR/LF (ENTER/new line/0x0D0A). Otherwise, what I am doing here is redirecting the output of the first command to the standard error stream. I then redirect the standard error stream into the standard input stream for the "set /p =" command.
Example:
(echo foo & echo.) >2 & (set /p bar=)<2
THIS DOESN'T USE PIPEs, but requires a single tempfile
I used this to put simplified timestamps into a lowtech daily maintenance batfile
We have already Short-formatted our System-Time to HHmm, (which is 2245 for 10:45PM)
I direct output of Maint-Routines to logfiles with a $DATE%@%TIME% timestamp;
. . . but %TIME% is a long ugly string (ex. 224513.56, for down to the hundredths of a sec)
SOLUTION OVERVIEW:
1. Use redirection (">") to send the command "TIME /T" everytime to OVERWRITE a temp-file in the %TEMP% DIRECTORY
2. Then use that tempfile as the input to set a new variable (I called it NOW)
3. Replace
echo $DATE%@%TIME% blah-blah-blah >> %logfile%with
echo $DATE%@%NOW% blah-blah-blah >> %logfile%
SUCCESSFUL TIMESYNCH [email protected]AFTER:
SUCCESSFUL TIMESYNCH 29Dec14@2252
ACTUAL CODE:
TIME /T > %TEMP%\DailyTemp.txt SET /p NOW=<%TEMP%\DailyTemp.txt echo $DATE%@%NOW% blah-blah-blah >> %logfile%
AFTERMATH:
All that remains afterwards is the appended logfile, and constantly overwritten tempfile. And if the Tempfile is ever deleted, it will be re-created as necessary.
The lack of a Linux-like backtick/backquote facility is a major annoyance of the pre-PowerShell world. Using backquotes via for-loops is not at all cosy. So we need kinda of setvar myvar cmd-line command.
In my %path% I have a dir with a number of bins and batches to cope with those Win shortcomings.
One batch I wrote is:
:: setvar varname cmd
:: Set VARNAME to the output of CMD
:: Triple escape pipes, eg:
:: setvar x dir c:\ ^^^| sort
:: -----------------------------
@echo off
SETLOCAL
:: Get command from argument
for /F "tokens=1,*" %%a in ("%*") do set cmd=%%b
:: Get output and set var
for /F "usebackq delims=" %%a in (`%cmd%`) do (
ENDLOCAL
set %1=%%a
)
:: Show results
SETLOCAL EnableDelayedExpansion
echo %1=!%1!
So in your case, you would type:
> setvar text echo Hello
text=Hello
The script informs you of the results, which means you can:
> echo text var is now %text%
text var is now Hello
You can use whatever command:
> setvar text FIND "Jones" names.txt
What if the command you want to pipe to some variable contains itself a pipe?
Triple escape it, ^^^|:
> setvar text dir c:\ ^^^| find "Win"
Source: Stackoverflow.com