Filename timestamp in Windows CMD batch script getting truncated

See Stack Overflow question How to get current datetime on Windows command line, in a suitable format for using in a filename?.

Create a file, date.bat:

@echo off
For /f "tokens=2-4 delims=/ " %%a in ('date /t') do (set mydate=%%c-%%a-%%b)
For /f "tokens=1-3 delims=/:/ " %%a in ('time /t') do (set mytime=%%a-%%b-%%c)
set mytime=%mytime: =% 
echo %mydate%_%mytime%

Run date.bat:

C:\>date.bat
2012-06-14_12-47-PM

UPDATE:

You can also do it with one line like this:

for /f "tokens=2-8 delims=.:/ " %%a in ("%date% %time%") do set DateNtime=%%c-%%a-%%b_%%d-%%e-%%f.%%g

The first four lines of this code will give you reliable YY DD MM YYYY HH Min Sec variables in XP Pro and higher, using WMIC.

@echo off
for /f "tokens=2 delims==" %%a in ('wmic OS Get localdatetime /value') do set "dt=%%a"
set "YY=%dt:~2,2%" & set "YYYY=%dt:~0,4%" & set "MM=%dt:~4,2%" & set "DD=%dt:~6,2%"
set "HH=%dt:~8,2%" & set "Min=%dt:~10,2%" & set "Sec=%dt:~12,2%"

set "datestamp=%YYYY%%MM%%DD%" & set "timestamp=%HH%%Min%%Sec%"
set "fullstamp=%YYYY%-%MM%-%DD%_%HH%-%Min%-%Sec%"
echo datestamp: "%datestamp%"
echo timestamp: "%timestamp%"
echo fullstamp: "%fullstamp%"
pause

Output example:

datestamp: "20200828"
timestamp: "085513"
fullstamp: "2020-08-28_08-55-13"
Press any key to continue . . .