environment variable string substitution
The command processor has some handy features that allow you to manipulate environment variables on the fly. For example, you can substitute one sub-string for another like this:
echo %myvar:sub1=sub2%
echo %time:0=-%
The second command would replace all "0"s with "-"s in the current system time.
You can also retrieve portions of the environment variable like this:
echo %time:~3,5%
This would display 5 characters of the system time begining at character 3, so if:
echo %time%
returns "01:23:45.67" then the previous command would return "23:45".
The big question is: how do you do both *without* setting a second environment variable to do it?
For example, suppose I want the middle 5 characters of the time (as above) but I also want to replace the colon(:) with an X instead?
I already know I can do this:
set temp=%time:~3,5%
echo %temp::=X%
this is what I am trying to avoid. :) Thanks!
echo %myvar:sub1=sub2%
echo %time:0=-%
The second command would replace all "0"s with "-"s in the current system time.
You can also retrieve portions of the environment variable like this:
echo %time:~3,5%
This would display 5 characters of the system time begining at character 3, so if:
echo %time%
returns "01:23:45.67" then the previous command would return "23:45".
The big question is: how do you do both *without* setting a second environment variable to do it?
For example, suppose I want the middle 5 characters of the time (as above) but I also want to replace the colon(:) with an X instead?
I already know I can do this:
set temp=%time:~3,5%
echo %temp::=X%
this is what I am trying to avoid. :) Thanks!
ASKER CERTIFIED SOLUTION
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ASKER
Ah-HA!
for /f "delims=." %t in ('echo %time::=%') do echo %t
This technically does what I want, but is more trouble than its worth to maintain.
for /f "delims=." %t in ('echo %time::=%') do echo %t
This technically does what I want, but is more trouble than its worth to maintain.
What exactly is it you want?
Seems like you want to echo the current time, but without the hundredth seconds?
That can be done without character substitution as well:
for /f "tokens=1-3 delims=:," %%a in ("%time%") do echo %%a%%b%%c
Then you probably want to print this several time in a script? Why not use a subroutine:
@echo off
:: ... Some batch script
call :echotime
sleep 2
call :echotime
:: ... Some batch script
goto leave
:: *** subroutine EchoTime
:: *** echoes the current time and returns
:EchoTime
for /f "tokens=1-3 delims=:," %%a in ("%time%") do echo %%a%%b%%c
goto :eof
:leave
Seems like you want to echo the current time, but without the hundredth seconds?
That can be done without character substitution as well:
for /f "tokens=1-3 delims=:," %%a in ("%time%") do echo %%a%%b%%c
Then you probably want to print this several time in a script? Why not use a subroutine:
@echo off
:: ... Some batch script
call :echotime
sleep 2
call :echotime
:: ... Some batch script
goto leave
:: *** subroutine EchoTime
:: *** echoes the current time and returns
:EchoTime
for /f "tokens=1-3 delims=:," %%a in ("%time%") do echo %%a%%b%%c
goto :eof
:leave
ASKER
Actually, it is simpler than that. All I'm trying to do is rename some files per the current date and time. I have a script that I tested yesterday afternoon and it worked fine, it renamed *.log to *.log.date_time
specifically the command expanded to this: ren filename.log filename.log.04262005_1544
But when the script ran overnight it failed because the %time% variable does not have a leading 0 before noon, so the rename command expanded to this: ren filename.log filename.log.04272005_ 73152
and the space messed up the rename command. Stand by and I'll post new code.
specifically the command expanded to this: ren filename.log filename.log.04262005_1544
But when the script ran overnight it failed because the %time% variable does not have a leading 0 before noon, so the rename command expanded to this: ren filename.log filename.log.04272005_ 73152
and the space messed up the rename command. Stand by and I'll post new code.
ASKER
this does it:
for /f "tokens=1,2,3,4,5,6,7,8* delims=/:_." %t in ('echo %time: =0%_%date:~4%') do ren *.log *.log.%z%y%x_%t%u%v
for /f "tokens=1,2,3,4,5,6,7,8* delims=/:_." %t in ('echo %time: =0%_%date:~4%') do ren *.log *.log.%z%y%x_%t%u%v
In that case, I'd suggest putting the date variable into reverse order, that is yyyymmdd; makes for easier sorting.
You can do that easily with a for /f command as well; the main configuration involves your date delimiter and the d/m/y order.
This should give you the basic idea:
for /f "tokens=1-3 delims=/" %%a in ("%date%") do (
set mm=%%a
set dd=%%b
set yy=%%c
)
set MyDate=%yy%%mm%%dd%
Adding leading zeroes to the hour is similar:
for /f "tokens=1-3 delims=:," %%a in ("%time%") do (
set hh=%%a
set mi=%%b
set ss=%%c
)
if %hh% LSS 10 set hh=0%hh%
set MyTime=%hh%%mi%%ss%
You can do that easily with a for /f command as well; the main configuration involves your date delimiter and the d/m/y order.
This should give you the basic idea:
for /f "tokens=1-3 delims=/" %%a in ("%date%") do (
set mm=%%a
set dd=%%b
set yy=%%c
)
set MyDate=%yy%%mm%%dd%
Adding leading zeroes to the hour is similar:
for /f "tokens=1-3 delims=:," %%a in ("%time%") do (
set hh=%%a
set mi=%%b
set ss=%%c
)
if %hh% LSS 10 set hh=0%hh%
set MyTime=%hh%%mi%%ss%
ASKER
actually, I mis-typed my original requirements, I should have specified this:
ren filename.log filename.log.20050426_1544
e.g.
ren filename.log filename.log.yyyymmdd_hhMM
but we've got it working now. Thanks!
ren filename.log filename.log.20050426_1544
e.g.
ren filename.log filename.log.yyyymmdd_hhMM
but we've got it working now. Thanks!
ASKER
for /f "tokens=1,2,3,4,5,6,7,8* delims=/:_." %t in ('echo %time: =0%_%date:~4%') do ren *.log *.log.%z%y%x_%t%u%v
this puts the date in the proper order and does not require extraneous variables beyond the scope of the for-statement.
this puts the date in the proper order and does not require extraneous variables beyond the scope of the for-statement.
ASKER
final version, simplified a bit:
for /f "tokens=1-6 delims=/:." %t in ('echo %date:~4%.%time: =0%') do ren *.log *.log.%v%t%u_%w%x%y
for /f "tokens=1-6 delims=/:." %t in ('echo %date:~4%.%time: =0%') do ren *.log *.log.%v%t%u_%w%x%y
ASKER
>> Why exactly do you want to get around the second variable?
Because I am an anal geek. Yep, that about sums it up. Just wanted to verify what I already suspected, thanks!