I need help with understanding the following Batch script structure:
This is named Profile_something_schedule.bat
call somePath\lib.cmd :someLabel reqPath
call somePath\lib.cmd :someLabel reqKey
%reqPath% "%~someFileName" /vv_pwd=%reqKey% /bProfile_something_schedule /min
I have a lot of difficulty understanding why this script works.
I do not know why the 3rd line is valid. The behavior produced is that the someFileName is run. I understand it as starting the file as a process. Then why isn't the start command needed? I don't see any batch documentation saying you can simply run a file by writing its pathed filename.
I do not understand the syntax of "%~someFileName". From online searching about it almost every source shows you the batch call parameter table, saying things like %~1 expands %1..., %~f1 expands %1 some other way, etc. All of them involve some kind of number from 0 to 9 to correspond to the parameter position. However, I cannot find any specification of %~someString being legal. There is no parameter positional information from the someFileName string, it is a filename.extension string. Still, it is quite likely this line is trying to run this format.
What does "/vv_pwd=%reqKey% /bProfile_something_schedule" mean? In the lib.cmd that was called previously, there were variables reqPath and reqKey and I am quite certain it is trying to pass the value of reqPath and reqKey from the lib.cmd into the variables here and then I guess it is trying to use the reqKey value as a parameter, which is a password required to run the file.
Inspecting the file, it contains some script of some paid software specific format, it only has variable name v_pwd inside but not vv_pwd. I do not know what the /bProfile_... is for. The part without the /b is exactly this batch file's name. But together with the /b I don't know what it means. The /v and /b look like some kind of options to me but I cannot see any specification explaining as there is no command beginning line 3 just some path. I guess the /min option refers to starting window minimized which is an option for the command start, yet there is no option of /v. The /B in start means to start application without creating window, which is quite unnecessary to have /min if you are not going to create a window in the first place. And it doesn't make sense to use /B directly followed by some string of Profile_something_Schedule.
FYI, the lib.cmd starts with call %*, which I would consider as trying to call all passed parameters and assuming those parameters are actually batch files that can be called.
Another thought I have is that the 2nd line call connects with the 3rd line so the 3rd line may not need a command. But I can't make sense of it. The someFileName is not of the Batch extension so I doubt it can be called as the call doc says it is for batch programs. If I want to run non-batch programs I need to use start right?
Would greatly appreciate your help!
The variable pathext contains a semicolon-separated list of executable filenames that may be appended as an extension to myexecutable. if the first string on a batch line is not a cmd internal command (like set, for etc.) then cmd tries to find myexecutable + each of the extensions in pathext in turn, first in the current directory, and then in each directory in the path (another semicolon-separated list of directories) and runs the first name found, or fails if none are found. That first string may also have an Associated extension, which then runs the application with which the extension is associated (like .txt runs notepad by default)
Neither do I, and I can't see that even knowing what the actual strings being executed by %reqPath% are would assist. See for /? from the prompt for more documentation on other ~ operators - or search SO for thousands of uses.
vv_pwd=%reqKey% : %reqKey% is replaced by the value of the variable reqKey evidently returned by the previous line. / is used in Windows to mean "here's a switch parameter for the executable", so evidently /vv_pwd=[the contents of reqKey], /bProfile_something_schedule and /min mean something to the executable %reqPath%. Quite what is anyone's guess.
The fact that lib.cmd's first line is call %* would mean that lib.cmd contains a library of routines. Since each call you have shown is of the form :string1 string2 then the resultant command executed would be call :string1 string2. call :string1 will call the routine contained within "lib.cmd" with the label string1: supplying string2 (and presumably optionally string2 string3... as parameters. Evidently, string2 is the name of the variable into which lib.cmd places the required data.
Without the :, string1 would be any executable that cmd can locate using the method in (1). It does not have to be a batch, but commonly is a batch.
Related
I'm using windows 10, running batch files through the command prompt window.
I can make things work, but I don't know why it works or why I can't do certain things:
set "file_list=a1 a2"
for %%a in (%file_list%) do (
echo %%a.py
)
This little piece of code works. I can build on it, BUT
Q1: I want to change the variable %%a to %%filename... but that doesn't work! I wondered if maybe filename were reserved, so I tried %%fname .
In this case I get the error:
%fname was unexpected at this time.
I can do a set fromm the command line and use a descriptive variable name, but it doesn't seem to work when looping. (I did it with the %file_list% variable above!) So how come I can only use a single character for a loop variable? Is there some way around that?
Q1a. This makes me think that the loop index variable is a different kind of variable that the ones in set commands. Is that correct? If so, is there a link that clearly and concisely explains the difference?
Q2. I notice the loop index variable is %%a, instead of a or %a or %a% . I never would have guessed this. The web sites I've looked at have just said, do this. But I can't see any explanation of why, except that the first percent is an escape. Okay. That doesn't really explain anything. It just means "this is how you do it." The error message when I use one percent sign is interesting.
set "file_list=a1 a2"
for %a in (%file_list%) do (
echo %a.py
)
"file_list) was unexpected at this time."
So I can vaguely see that maybe something isn't being escaped correctly. Why does that % in the %a need to be escaped, so it becomes %%a ?
A for meta-variable must consist of % (in Command Prompt) or %% (in a batch file) and a single character (case-sensitive letter), like %a or %%a. You cannot define %filename or %%filename.
Loop variables only exist within the respective for loop. Do not confuse such loop variables with normal environment variables, like %TEMP%, for example, which are available globally.
There are these things marked by %-signs:
%-escaping (only applicable for batch files), so %% denotes one literal %-sign;
command line arguments/parameters (only applicable for batch files, obviously), like %1;
immediately expanded environment variables*, like %TEMP%;
for meta-variables, like %a (in Command Prompt) or %%a (in batch files), which are specific to the for command, so they do not exist outside of the related loop context;
%-escaping (1.) happens before expanding for meta-variables (4.), hence actually the for command receives a loop variable like %a.
Then environment variables (3.) are treated differently in Command Prompt and in batch files: the former keeps undefined variables literally, the latter removes them.
The detailed parsing rules can be found in this post, which have been implemented by Microsoft (or IBM?) that way in order to be able to distinguish between the different %-things, so at the end it was their decision, therefore you have to ask them for the exact reason…
*) There is also something like delayed environment variable expansion, but this uses !-signs to mark the variables, like !TEMP!, and this is something that happens after all the %-sign expressions have been parsed.
I was making a batch file to take dragged-and-dropped folders for program input. Everything was working fine until I passed a folder, which for the sake of this post, called foo&bar.
Checking what %1 contained inside the batch file looked like C:\path\to\foo or C:\path\to\foo\foo. If the file path were in quotes it would work, so the only working code that slightly takes this into effect is :
set arg1=%1
cd %arg1%*
set arg1="%CD%"
Which changes directory to the passed argument using wildcards. However this only works once for if there is another folder with un-escaped characters inside the parent folder, passing the child folder would result in the parent folders' value.
I tried the answer of this post, which suggests to output the argument using a remark and redirection statement during an #echo on sequence. However no progress occurred in rectifying the problem. Any suggestions?
To recap, I am looking for ways to pass folders with un-escaped characters as arguments to a batch file. The implementation should preferably be in a batch file, but answers using VBScript are welcome. However the starting program must be in batch as this is the only program of the 3 that accepts files as arguments.
To test this, create a batch file with following code:
#echo off
set "arg1=%~1"
echo "the passed path was %arg1%"
pause
Then create folders called foobar and foo&bar. Drag them onto the batch file to see their output. foo&bar will only return C:\path\to\foo.
OK, so the problem is that Explorer is passing this as the command line to cmd.exe:
C:\Windows\system32\cmd.exe /c ""C:\path\test.bat" C:\path\foo&bar"
The outermost quotes get stripped, and the command becomes
"C:\working\so46635563\test.bat" C:\path\foo&bar
which cmd.exe interprets similarly to
("C:\working\so46635563\test.bat" C:\path\foo) & bar
i.e., bar is considered to be a separate command, to be run after the batch file.
The best solution would be to drag-and-drop not directly onto the batch file but onto, say, a vbscript or a Powershell script or a plain old executable. That script could then run the batch file, either quoting the argument appropriately or putting the directory path into an environment variable rather than on the command line.
Alternatively, you can retrieve the original command string from %CMDCMDLINE% like this:
setlocal EnableDelayedExpansion
set "dirname=!CMDCMDLINE!"
set "dirname=%dirname:&=?%"
set "dirname=%dirname:" =*%"
set "dirname=%dirname:"=*%"
set "dirname=%dirname: =/%"
for /F "tokens=3 delims=*" %%i in ("%dirname%") do set dirname=%%i
set "dirname=%dirname:/= %"
set "dirname=%dirname:?=&%"
set dirname
pause
exit
Note the exit at the end; that is necessary so that cmd.exe doesn't try to run bar when it reaches the end of the script. Otherwise, if the part of the directory name after the & happens to be a valid command, it could cause trouble.
NB: I'm not sure how robust this script is.
I've tested it with the most obvious combinations, but YMMV. [It might be more sensible to use delayed expansion exclusively, I'm not sure. It doesn't seem to be necessary except in the first set command. Jeb's answer here might be a better choice if you're going this route.]
For the curious, the script works like this:
Load the original command line into dirname [necessary for the reason pointed out by jeb]
Replace all the & characters with ?
Replace all the quote marks with *
If a quote mark is followed by a space, suppress the space.
NB: it is necessary to suppress the space to deal with both the case where the path contains a space (in which case Explorer adds quote marks around it) and the case where it doesn't.
Replace all remaining spaces with /
NB: ? * and / are illegal in file names, so these replacements are safe.
At this point the string looks like this:
C:\Windows\system32\cmd.exe//c/**C:\path\test.bat**C:\path\foo?bar**
So we just need to pull out the third asterisk-delimited element, turn any forward slashes back into spaces and any question marks back into ampersands, and we're done. Phew!
I'm writing a CMD script to execute a Java program. The program requires at least one argument so I created an if else block to check that argument one %1 is not blank. When I run the script without providing argument one I get the expected you must provide an argument to run. But when I do provide the argument the program does not execute. Additionally if I don't have #echo off set, the entire script prints out as text in the window when I do provide the proper argument.
Here's the full script:
set APP_HOME=C:\Temp\Hammer
rem Set APP_HOME to the place where you installed Hammer
if ["%1"] == [""] (
echo you must provide a python script to run
) else (
java -cp %APP_HOME%\lib\jython.jar;%APP_HOME%\lib\hammer.jar;%CLASSPATH% bridenstine.hammer.main.Main %1 %2
)
I think this is a problem with the script and not the program itself because when I run the line that's in the else block by itself without the script,
java -cp C:\Temp\Hammer\lib\jython.jar;C:\Temp\Hammer\lib\hammer.jar;%CLASSPATH% bridenstine.hammer.main.Main argument1
The program executes normally. I've been looking at example scripts and cross referencing this site for CMD files and what I have seems to be valid. Do I have a syntax error?
Update:
I'm running the script like so,
cd C:\Temp\Hammer
bin\ProgramScript.cmd argument1
Update 2:
Someone pointed out that when they run this script they get an error message saying Java is not recognized as an internal or external command (the expected message when Java is not set on their PATH) But they made a good point that this means the script is in fact getting inside the else block. I then pointed out the following,
After I run the script with a valid argument it prints out the entire script as text on the command prompt. I am then able to mark the line from inside the else statement (that was printed), copy it, paste it, and it runs the program fine. So the Java command seems to be valid. But you make a good point that the script is obviously getting inside the else block...something is still going wrong here and it doesn't seem to be the program.
Note:
If relevant I am using Windows 8.1 and I am using the standard command prompt, not one that has administrative privileges (the results remained the same regardless of using a command prompt with administrative privileges).
I suggest to use
set APP_HOME=C:\Temp\Hammer
rem Set APP_HOME to the place where you installed Hammer.
if "%~1"=="" (
echo You must provide a Python script to run.
pause
) else (
java.exe -cp "%APP_HOME%\lib\jython.jar;%APP_HOME%\lib\hammer.jar;%CLASSPATH%" bridenstine.hammer.main.Main %*
)
It is always better to enclose an argument string in double quotes if it contains environment variables like CLASSPATH which might have a string value containing 1 or more spaces.
%* is expanded by all arguments passed to the batch file as argument, i.e. %1 %2 ...
It is best to always specify an application like java with full path and file extension as otherwise Windows has to search for a file with a file extension as defined in environment variable PATHEXT in current working directory and all directories defined in environment variable PATH. At least the file extension should be in the batch file if the program files directory of the application varies.
I can only offer a suggestion; I've not tried this.
I would try escaping each ; with a caret ^ thus:
java -cp %APP_HOME%\lib\jython.jar^;%APP_HOME%\lib\hammer.jar^;%CLASSPATH% bridenstine.hammer.main.Main %1 %2
(But I'll admit it's clutching at straws...)
You are missing you she-bang at the top of the script
#!/bin/bash
I have an exe file. I want to run it several times repeatedly one after another. I tried below batch file but couldnt do it is there a way to do it? Sorry but i am a rookie in code writing
#echo off
start ran.exe
start ran.exe
start ran.exe
Assuming that ran.exe is in the current folder or on your path, then you simply write:
#echo off
ran
ran
ran
to invoke it three times. If it is not found on the PATH, then use a fully qualified name like this:
#echo off
c:\path\to\ran
c:\path\to\ran
c:\path\to\ran
Running a program is the normal effect of naming it on a line of a batch file.
Furthermore, because .EXE is listed in the PATHEXT environment variable, you don't need to include that in the name, unless there is also a file name ran.com since .COM is listed in the default value of PATHEXT ahead of .EXE.
The START builtin command is only needed in batch files for handling some special cases. See the output of START /?1 for its documentation. In general, you don't need it just to launch programs.
Update: To generalize this to N invocations, use the FOR command. FOR is extremely powerful, type FOR /? at the command prompt for documentation. For N repeats specified as the argument to the batch file, and passing the current count to the command as its first argument do this:
#echo off
for /L %%N in (1,1,%1) do c:\path\to\ran %%N
The tricky thing to remember with FOR is that the iteration variable must be named with two percent signs in batch files. The help text says that, but only in passing.
Update 2: Some more details and explanation.
In this case, we want to repeat a command N times. FOR supports a variety of kinds of loops, but the easiest way to get exactly N iterations is to use its /L option which uses a starting value, a step size, and an ending value to define the number of iterations.
These are specified in parenthesis, as FOR /L %%N (start,step,end). To get a simple counter of 1 to N, we tell it to start at 1, step by 1, and to stop at the value of the first argument to the batch file which is named %1.
The arguments to the batch file itself are named as %1 through %9, and %* names all of the arguments. Note that there is a vast minefield of subtlety here related to properly quoting file names that contain spaces. To keep life simple, try very hard not to need to do that. Otherwise, CALL /? documents the command line argument conventions, and SET /? documents many things related to general batch file variables.
Other forms of FOR let you iterate over files (no option), directories (/D), directories recursively in a tree (/R), or various parts of the contents of files (/F).
If from inside a bat file you called another batch file but still had a few remaining operations to complete, how can you make sure that the call to first bat file will after completion or error, will return to the file that called it in the first instance?
Example:
CD:\MyFolder\MyFiles
Mybatfile.bat
Copy afile toHere
or
CD:\MyFolder\MyFiles
CALL Mybatfile.bat
COPY afile toHere
What is the difference between using CALL or START or none of them at all? Would this have any impact on whether it would return for the results of the copy command or not?
As others have said, CALL is the normal way to call another bat file within a .bat and return to the caller.
However, all batch file processing will cease (control will not return to the caller) if the CALLed batch file has a fatal syntax error, or if the CALLed script terminates with EXIT without the /B option.
You can guarantee control will return to the caller (as long as the console window remains open of course) if you execute the 2nd script via the CMD command.
cmd /c "calledFile.bat"
But this has a limitation that the environment variables set by the called batch will not be preserved upon return.
I'm not aware of a good solution to guarantee return in all cases and preserve environment changes.
If you really need to preserve variables while using CMD, then you can have the "called" script write the variable changes to a temp file, and then have the caller read the temp file and re-establish the variables.
call is necessary for .bat or .cmd files, else the control will not return to the caller.
For exe files it isn't required.
Start isn't the same as call, it creates a new cmd.exe instance, so it can run a called batch file asynchronosly
The `CALL' statement was introduced in MS-DOS 3.3
It is used to call other batch files within a batch file, without aborting the execution of the calling batch file, and using the same environment for both batch files.
So in your case the solution is to use CALL
Okay, I actually didn't even really think about the fact that if you call a batch (regardless of the 'type', i.e. '.bat', or '.cmd') that it won't return if you don't use call.
I've been using call myself though for a different reason that I am actually pretty surprised that no one else has brought up. Maybe I missed it. MAYBE I'M THE ONLY ONE IN THE WORLD WHO KNOWS!! :O
Probably not, but I'm going to drop this knowledge off here because it's super useful.
If you use call you can use binary logic operators to decide how to proceed based on the ERRORLEVEL result. In fact, I always was flabbergasted on how && and || existed in DOS and COULDN'T be used this way. Well, that's why.
The easiest way to test this is to create a return.cmd with notepad, or from the command prompt like so:
c:\> type con >return.cmd
You will now notice the cursor goes down to the next line and hangs. Enter:
#exit /B %1
And then hit ENTER, and then CTRL-Z and that file will be created. Good! You may now feel free to try the following two examples:
call return.cmd 0 && echo Huzzah! A Complete Success! (Or cover up...)
call return.cmd 123 || echo Oops! Something happened. You can check ERRORLEVEL if you want the tinest amount of additional information possible.
So what? Well, run them again with the 0 and the 123 swapped and you should see that the messages DON'T print.
Maybe this multi-line example will make more sense. I use this all the time:
call return.cmd 0 && #(
echo Batch says it completed successfully^^!
) || #(
echo Batch completed, but returned a 'falsey' value of sort.
call echo The specific value returned was: %ERRORLEVEL%
)
(Note the 'call' in the || section before the second 'echo'. I believe this is how people got around not having delayed expansion back in the day. If you DO have delayed expansion enabled (via. setlocal EnableDelayedExpansion inside a batch OR launch a command prompt with cmd /v:on then you can just do !ERRORLEVEL!.)
... This is where I have to apologize and say if you have if ERRORLEVEL trauma in your past you should stop reading. I get it. Trust me. I thought about paying someone on fiverr to remotely type this for me, but for completeness sake I'm just going to take one for the team and mention that you can also do the following to check errorlevel:
if ERRORLEVEL 123 #echo QUICK! MOTHERS, COVER YOUR CHILDREN'S EYES! FINGERS ARE BEING UNDONE! :'(
If you've never typed that before then GOOD! You will live longer without having to read up why exactly you aren't getting the results you expect. Cruel is the word you're looking for, not 'quirky'.
The important part that I really want to get across however is that if you try this and DON'T use 'call' it will ALWAYS execute the 'true' branch. Try it for yourself!
If I'm missing something, or you know a better way to do this, please let me know. I love learning stuff like this!
Additional information I mentioned:
I have known for quite some time that you can put redirects BEFORE commands like so:
>nul echo. This won't be displayed!
But I accidentally discovered the other day by being a dumdum that you can apparently also do:
echo A B>file.txt C
And was REALLY surprised to find a file.txt which consisted of "A B C". It appears yo can place them ANYWHERE, even inside the command. I've never seen anyone do this, nor mention it, but I HAVE seen people mention that you can prefix a line with them.
Maybe it's a bug exclusive to Windows 10 or something. If you have another version and wanna try it out and let me know I'd be interested in what you find out.
Stay nerdy!