Programming in a batch script - windows

Hey all I have a simple problem I was hoping someone can give me assistance with. I'm trying to get WMIC to return output however on different machines, the executable is in different directories. Is there a method to check all directories I list to get it to run, e.g.:
IF EXIST
wmic=c:\checkhere\
ELSE
wmic=c:\checkthisone\
CONTINUE

The following is a simple way of setting an environment variable to some path that has a file you are looking for. A rather brain dead way but easy to understand/change:
if exist c:\path1\some.exe set asdf=c:\path1\
if exist c:\path2\some.exe set asdf=c:\path2\
if exist c:\path3\some.exe set asdf=c:\path3\
if %asdf%x=x goto couldnotfindit
set path=%path%;%asdf%

As an option You could add all of them to the PATH variable and simply run wmic.

Related

Environmental variables - how to check in runtime which command is executed

I have got multiple env. variables set in PATH; I am also using .bat files to set these before certain activities. It's obvious that some variables may be then duplicated ex. grep may be defined more than once (in cygwin and MSYS2) For sure there is a way to check which file i have executing using specific command and which other files are available, based on PATH. Could you please suggest the way to do this?
Thanks in advance.
The nearest to kpathsea on windows is where
where /t cmd.* grep.* notepad.*
to check in the path use
where /t $path:cmd*
for a listing of most possibilities try
where /t $path:*>commands.txt

Execute Batch Script From Environment Variable

I've set an system environment variable called find which points to a batch script. I did this so that in Win command prompt i could type %find% and it would execute my script. It works the only problem is it only works once, my script takes a parameter or requires user input (have tried both), and then it is as if the %find% is temporarily overwritten, and the %find% of course no longer works, until i reopen the command window. Basically it works once and that's it!
How can i make it work every time? i want to execute my script using the environment variable over and over again at will without reloading the command window.
Thanks.
I created a batch script with the following code:
#ECHO off
echo hello
and added a environmental variable called TEST that points to the script. I have no problem executing the script using the environmental variable multiple times.
Can you please provide some information or code of what your script does?
Remember that find is a MS-supplied utility.
Try using a different name. And show us your batch - even possibly describe what happens when it "no longer works." Games of 20-questions are tedious.
The problem is that the Batch script uses a variable with the same name, so after it run for the first time the variable value is overwritten and no longer works. To prevent this to happen, insert a setlocal command at beginning of the Batch file; this way, when the script ends all variables are reset to the values they had before the script run. This method also delete all new variables defined in the Batch script, so it keep the environment clean.
If your intention is to override the behavior of the existing find.exe utility, you could add the location of the script to the global path variable before your System32 folder (where find.exe is located). For example, let's say your script is C:\Scripts\find.bat. If your path variable is currently set to this:
%SystemRoot%\system32;%SystemRoot%
...then you would change it to this:
C:\Scripts;%SystemRoot%\system32;%SystemRoot%
Beware though... doing this could break other scripts that use the find command (if they don't use the absolute path to find.exe).
If you are just wanting an easy way to run your alternate find command, you could just give it a different name as the others have suggested, then add it to the end of the path or place it in the System32 folder. That would save you from having to type the percent signs at least.

How to do a for loop in windows command line?

I was wondering if this was possible? I'm not familiar with using windows command line, but I have to use it for a project I'm working on. I have a a number of files, for which I need to perform a function for each. I'm used to working with python, but obviously this is a bit different, so I was hoping for some help.
Basically I need the for loop to iterate through 17 files in a folder, perform a function on each (that's using the specific software I have here for the project) and then that will output a file with a unique name (the function normally requires me to state the output file name) I would suck it up and just do it by hand for each of the 17, but basically it's creating a database of a file, and then comparing it to each of the 17. It needs to be iterated through several hundred times though. Using a for loop could save me days of work.
Suggestions?
The commandline interpreter does indeed have a FOR construct that you can use from the command prompt or from within a batch file.
For your purpose, you probably want something like:
FOR %i IN (*.ext) DO my-function %i
Which will result in the name of each file with extension *.ext in the current directory being passed to my-function (which could, for example, be another .bat file).
The (*.ext) part is the "filespec", and is pretty flexible with how you specify sets of files. For example, you could do:
FOR %i IN (C:\Some\Other\Dir\*.ext) DO my-function %i
To perform an operation in a different directory.
There are scores of options for the filespec and FOR in general. See
HELP FOR
from the command prompt for more information.
This may help you find what you're looking for...
Batch script loop
My answer is as follows:
#echo off
:start
set /a var+=1
if %var% EQU 100 goto end
:: Code you want to run goes here
goto start
:end
echo var has reached %var%.
pause
exit
The first set of commands under the start label loops until a variable, %var% reaches 100. Once this happens it will notify you and allow you to exit. This code can be adapted to your needs by changing the 100 to 17 and putting your code or using a call command followed by the batch file's path (Shift+Right Click on file and select "Copy as Path") where the comment is placed.
You might also consider adding ".
For example for %i in (*.wav) do opusenc "%~ni.wav" "%~ni.opus" is very good idea.

Batch- string search on Windows PATH

I am writing an batch file in Windows to run post-installation scripts, and one of the things that needs to be done is to add a directory to the system path.
The script is working, and it does something like this:
setx Path "%PATH%;c:\path\to\add" -m
This is setting the path correctly, but this script could potentially be run multiple times if the user reinstalls the program.
I would like to search the string for c:\path\to\add so I don't keep adding the same path over and over to the system path. This is pretty trivial in Linux with sed, but I don't know what the command is in Windows. I've found findstr, but this seems to only work on files.
Is this possible in Windows without installing additional software?
EDIT:
I'm using Inno Setup to create the install executable.
At the risk of some downvotes till an expert provides a sound way of doing this,
the below removes the specific path from the environment variable if it exists, so that it can be added again:
set str=%path%
:: str is the same with path
set str=%str:;C:\Path\To\Add=%
:: ";c:\path\to\add" is now removed from str
setx Path "%str%;c:\path\to\add" -m
:: proceed with setting the path
This carries the risk of removing the string if it is in fact actually a part of a path, for instance c:\path\to\add\somefolder. Also if the path actually ends with a \, or it is the first entry and it in fact does not start with ;, etc..
Various forms can be called consecutively to circumvent some of these,
set str=%str:;C:\Path\To\Add\;=;%
set str=%str:;C:\Path\To\Add;=;%
set str=%str:;C:\Path\To\Add\=%
set str=%str:C:\Path\To\Add\;=%
set str=%str:;C:\Path\To\Add=%
But, AAMOF I'n not sure this is a sane way of doing this..
This is my code snippet to find the "cvsnt" path in the PATH variable.
if not "x%PATH:cvsnt=%" == "x%PATH%" goto proceed
set PATH=w:\build-repository\cvsnt\2.5.03-2382;%PATH%
echo Path added
:proceed
The part to look at is
not "x%PATH:cvsnt=%" == "x%PATH%"
First I replace all occurrences of "cvsnt" with an empty string. The result is compared to PATH without replacement of "cvsnt". If they are not equal because of "cvsnt" was replaced then it exists in PATH and the code can proceed.
The starting x before %PATH% is only a placeholder to protect against certain "improper" starting characters. see Batch file: Find if substring is in string (not in a file)
The setx utility has a drawback, it can not handle variables longer than 1024 characters.
I have been wrote a script to handle cases longer than the limit and without a need to install anything. Answered the question here: Set environment variables with NSIS in Window 7
Instead of adding the path each time - you could check if the executable you are looking for can be found within the path using a command like this:
for %f in (cmd.exe) do if [%~$PATH:f]==[] setx Path "%PATH%;c:\path\to\add" -m
Make sure to check for /? to read more about the magic of %~$PATH:f.
This is a bit of a hackish workaround, but follows the logic you expect:
Search the PATH
Conditionally add to the PATH
It never removes anything from the PATH, so there's no fear of screwing up Windows by removing something accidently. Also, it checks the PATH variable directly, so you don't have to worry about another file with the same name that lives somewhere on the PATH.
echo %PATH% > myTmpPath.tmp
find /C /I "c:\path\to\add" myTmpPath.tmp
if %ERRORLEVEL% neq 0 setx PATH "%PATH%;c:\path\to\add"
del myTmpPath.tmp
I hate using temporary files, but it's quick and dirty, and probably safer than removing something from the PATH.
The third line is the only tricky one. Basically, this line tests the outcome of the FIND command above. Rob van der Woude states:
FIND returns an errorlevel of 1 or higher if the search string wasn't found.
He also explains:
Some executables return negative numbers for errorlevels! However, this can be
fixed by using the following code to check for non-zero return codes:
IF %ERRORLEVEL% NEQ 0 ...

CMD: Fails with %1

Recently i posted a question about what the variable is of a file which you open with a batch file, which is %1.
I used this, to let my batch file copy %1 to a specific location.
After doing this, debugging and a lot of time, and it actually worked, after debugging it more, adding some features, and some more debugging, it stopped working. This is a snippet, where it seems it goes wrong (i tried #echo on to get my info.)
if not "%1:~-8%"==".package" (
set error=yes
set errmes1=File %1 does not have a .package extension.
goto :errpkg
)
copy "%1" "C:\path_to\folder"
:errpkg
cls
echo %errmes1%
...
(%1=C:\path\to\it\file_something.package)
This is the point were it goes wrong, i guess. Because it ends up with this message. What it SHOULD do, is at if not checking if the file has a .package extension. then, set error=yes, just says what it does, set errmes1 sets an error message. and then the goto just goes to some place in the batch file where it explains what the problem is. (using %errmes1%)
So, that's it. Here is where it goes wrong. I am 100% sure it has a .package extension. Could anyone help me, to tell me what the problem is?
I seriously wonder how you ever got that to work. The substring syntax only works on environment variables (well, and pseudo-variables such as %cd%). That means you can do
%foo:~-8%
but not
%1:~-8%
This wouldn't even work if you had an environment variable named %1%.
Anyway, the usual idiom to check for the extension of an argument is
%~x1
So why complicate things more than necessary?
Tried using %~x1 to extract the extension? Your syntax doesn't work for me.
Also, can't setting variables inside the conditional get screwy in cmd.exe?

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