How to add time stamp to log lines in log file from batch file output?

Question

I want to add time stamp to log lines from batch output.

Here is my batch file:

@Echo off
SET LOGFILE=MyLogFile.log
call :Logit >> %LOGFILE% 
exit /b 0

:Logit
set "affix=%date%_%time%"
set "affix=%affix::=%"
set "affix=%affix:/=%"
xcopy "I:\DF\AB\Data.xlsx" "D:\TL\BACKUP\Data_%affix%.xlsx"*

Output of log file:

I:\DF\AB\Data.xlsx
1 File(s) copied

I want output log file looking like this:

I:\DF\AB\Data.xlsx
20180831_124500 : 1 File(s) copied

How could this be achieved?

Some more information:

1. The asterisk at end of target argument string is required for copying the file without prompt. There would be a prompt asking if target is a file or a directory if * would not be used at end of target file name.
2. xcopy is used because copied is a file from a network drive to local drive.

The output result is as below after running the batch file:

I:\DF\AB\Data.xlsx
08312018_163959.07 :I:\DF\AB\Data.xlsx
1 File(s) copied

May it be as below?

I:\DF\AB\Data.xlsx
08312018_163959.07  1 File(s) copied 

So the region dependent date format is MM/DD/YYY and time format is HH:mm:ss.ms.

Answer 1

I suggest following code producing exactly the initially wanted output in log file:

@echo off
setlocal EnableExtensions DisableDelayedExpansion
set "LOGFILE=MyLogFile.log"
del "%LOGFILE%" 2>nul
call :Logit >>"%LOGFILE%"
endlocal
exit /B 0

:Logit
set "FileDate=%DATE:~-4%%DATE:~-10,2%%DATE:~-7,2%_%TIME:~0,2%%TIME:~3,2%%TIME:~6,2%"
for /F "tokens=1* delims=:" %%I in ('%SystemRoot%\System32\xcopy.exe "I:\DF\AB\Data.xlsx" "D:\TL\BACKUP\Data_%FileDate%.xlsx*" /C /V /Y 2^>nul') do (
    if not "%%J" == "" (
        echo %%I:%%J
    ) else (
        echo %FileDate% : %%I
    )
)
goto :EOF

The region dependent date and time is reformatted to yyyyMMdd_HHmmss by using string substitutions of the dynamic environment variables DATE and TIME as explained in detail for example by the answer on the question: What does %date:~-4,4%%date:~-10,2%%date:~-7,2%_%time:~0,2%%time:~3,2% mean? For a much slower, but region independent solution, to get date/time in a specific format see for example the answer on: Why does %date% produce a different result in batch file executed as scheduled task?

The current date and time in format yyyyMMdd_HHmmss is assigned to the environment variable FileDate used twice on the next line, once in name of target file and once more in output of last line of reformatted output of command XCOPY.

The XCOPY command line used here is for example:

C:\Windows\System32\xcopy.exe "I:\DF\AB\Data.xlsx" "D:\TL\BACKUP\Data_20180831_163959.xlsx*" /C /R /V /Y 2>nul

This command line is executed by FOR in a separate command process started by FOR with cmd.exe /C in background. FOR captures all lines written to handle STDOUT of this command process before processing the captured lines.

XCOPY outputs to handle STDOUT the names of the copied files with full path and as last line a summary information. Errors on file copying are written to handle STDERR which are suppressed by redirecting them to device NUL.

Read also the Microsoft article about Using command redirection operators for an explanation of 2>nul. The redirection operator > must be escaped with caret character ^ on FOR command line to be interpreted as literal character when Windows command interpreter processes this command line before executing command FOR which executes the embedded xcopy command line with using a separate command process started in background.

The asterisk * at end of target file name should be within the double quotes of second argument string and not outside because otherwise cmd.exe respectively xcopy.exe has to correct this wrong syntax.

Please note that the trick with * at end of target file name works here by chance because source and target file have same file extension and the source file name is always shorter than the target file name. Otherwise the command would fail or target file gets an unwanted name being a concatenation of target file name + the characters of source file name after n characters of target file name.

In general there are better methods to avoid a halt on prompt which XCOPY requests in case of a single file is copied with a new file name. The letter to answer the prompt can be output first to STDOUT redirected to handle STDIN of XCOPY command as demonstrated language independent in answer on batch file asks for file or folder.

The captured output of XCOPY is processed by FOR line by line with skipping empty lines and lines starting with a semicolon ; as being the default end of line character of option eol= not used here.

The goal here is to output all lines with a full qualified file output by XCOPY in background command process also in this command process, but output the last line with the summary information different by prepending it with the date/time in wanted format, a space, a colon and one more space.

For that reason the default line splitting behavior on spaces/tabs with assigning only first substring (token) to specified loop variable I is modified here by the options tokens=1* delims=:. FOR splits up a line on colons now.

Only the lines with a full qualified file name starting with a drive letter and a colon contain a colon at all. On such lines the drive letter is assigned to specified loop variable I as specified by tokens=1. The rest of a file name line after first colon is assigned without any further splitting to next loop variable according to ASCII table to loop variable J which is here everything after the colon after drive letter.

The summary information line does not contain a colon. For that reason FOR assigns the entire summary information to loop variable I and J holds an empty string.

The loop variable J is never empty on a line with a file name starting with a drive letter and a colon. This fact is used here to determine if the line from XCOPY should be output as is with inserting the removed colon between drive letter and file path + file name + file extension or output the summary information with date/time at beginning.

Please note that this method works only on copying files from a drive with a drive letter. A different method would be necessary for source files with a UNC path.

In fact copying a single file can be done much easier with command COPY instead of XCOPY even from/to a network drive or when source/target file name is specified with a UNC path. COPY has also the options /V and /Y and even /Z like XCOPY. COPY does not create the target directory structure like XCOPY, but this can be done with command MD before. COPY can't overwrite a read-only file as XCOPY can do on using option /R, but this limitation of COPY is most likely not relevant here. And COPY does not copy a file with hidden attribute set. However, in general copying a single file is nevertheless best done with command COPY instead of XCOPY.

So here is one more solution with using command COPY which is faster than the XCOPY solution as there is no reason for executing the file copy in a separate command process, capture any line, split them and output them concatenated again or modified.

@echo off
setlocal EnableExtensions DisableDelayedExpansion
set "LOGFILE=MyLogFile.log"
md "D:\TL\BACKUP" 2>nul
del "%LOGFILE%" 2>nul
call :Logit >>"%LOGFILE%"
endlocal
exit /B 0

:Logit
set "FileDate=%DATE:~-4%%DATE:~-10,2%%DATE:~-7,2%_%TIME:~0,2%%TIME:~3,2%%TIME:~6,2%"
echo I:\DF\AB\Data.xlsx
copy /B /V /Y "I:\DF\AB\Data.xlsx" "D:\TL\BACKUP\Data_%FileDate%.xlsx" >nul 2>nul && echo %FileDate% : 1 File(s) copied|| echo %FileDate% : 0 File(s) copied
goto :EOF

This solution has also the advantage that the line output on success or error can be fully customized. COPY exits with a value greater 0 on an error like source file not available or target file/directory is write-protected currently or permanently.

Example of a better output for a single copied file on success or error (subroutine only):

:Logit
set "FileDate=%DATE:~-4%%DATE:~-10,2%%DATE:~-7,2%_%TIME:~0,2%%TIME:~3,2%%TIME:~6,2%"
copy /B /V /Y "I:\DF\AB\Data.xlsx" "D:\TL\BACKUP\Data_%FileDate%.xlsx" >nul 2>nul
if not errorlevel 1 (
    echo %FileDate% : Copied successfully I:\DF\AB\Data.xlsx
) else (
    echo %FileDate% : Failed to copy file I:\DF\AB\Data.xlsx
)
goto :EOF

It is of course also possible to use the command line

set "FileDate=%DATE:/=%_%TIME::=%"

in the batch file to get the date and time in format MMddyyyy_HHmmss.ms if that is really wanted now. I don't recommend this date/time format as it is not good on alphabetical list of all Data_*.xlsx files in directory D:\TL\BACKUP. The list of files sorted by name is with the date/time format yyyyMMdd_HHmmss automatically also sorted by date/time.

For understanding the used commands and how they work, open a command prompt window, execute there the following commands, and read entirely all help pages displayed for each command very carefully.

• call /?
• copy /?
• del /?
• echo /?
• endlocal /?
• exit /?
• for /?
• goto /?
• if /?
• md /?
• set /?
• setlocal /?
• xcopy /?

See also:

• Where does GOTO :EOF return to?
• Single line with multiple commands using Windows batch file for an explanation of the operators && and ||.

Answer 2

powershell -command "(New-TimeSpan -Start (Get-Date "01/01/1970") -End (Get- Date)).TotalSeconds">LOG.TXT

Although this is not the format you suggested, this format is called epoch time.
The good thing about this format is that it is always a float value.

LOG.TXT will be the name of the log, make sure you are in the right directory.

Answer 3

You can use echo| set /p=%affix% to eliminate the newline at echo time as:

@Echo off
SET LOGFILE=MyLogFile.log
call :Logit >> %LOGFILE% 
exit /b 0
:Logit
set "affix=%date%_%time%"
set "affix=%affix::=%"
set "affix=%affix:/=%"
echo|set /p=%affix% :
xcopy "I:\DF\AB\Data.xlsx" "D:\TL\BACKUP\Data_%affix%.xlsx"*

Result:

I:\DF\AB\Data.xlsx
2018-08-31_124900 :        1 file(s) copied.

Answer 4

You're only XCopying one file, so you know that your last line of output on success will be the language dependent string 1 File(s) copied.
As you've already limited the script to using a locale dependent %DATE% and %TIME%, I have assumed that language dependency for this task is fine.

Here therefore is a ridiculous looking example script:

@Echo Off
Set "srcfile=I:\DF\AB\Data.xlsx"
Set "destdir=D:\TL\BACKUP"
Set "logfile=MyLogFile.log"

For %%A In ("%srcfile%") Do Set "dstname=%%~nA" & Set "destext=%%~xA"

For /F "Tokens=1-2 Delims=|" %%A In ('
    Echo F^|XCopy "%srcfile%" "|%DATE:/=%_%TIME::=%|" /L 2^>Nul ^&^
    Echo F^|Xcopy "%srcfile%" "%destdir%\%dstname%_%DATE:/=%_%TIME::=%%destext%" /Y ^>Nul 2^>^&1
') Do (If Not "%%B"=="" Set "_=%%B"
    If Defined _ If /I "%%A"=="%srcfile%" ((
            Echo %%A&Call Echo %%_%%  1 File(s^) copied)>"%logfile%"))

You should change nothing other than the values for the variables on lines 2-4.
However should you be using an existing logfile, you may wish to change > on the last line to >>