I know how to add values to the path variable, so my question is not how to use it.
Rather, I want to know how it works under the hood. When you type in the name of a program to execute, how does the system make use of PATH to find the matching program? How does it know when it finds a match?
for example...
when you set c:\python27\ into your environment path...
and you goto cmd, you are at c:\ and you type python
cmd knows to check the environment path which it will find c:\python27\ among others. then it looks for the command in each path listed in your environment paths
then executes the command if it finds it
simply the env path tells where to look for the command if it is not in the current directory
I am running the following SQL query through a powershell script and need to run the script multiple times against different files. So what I am trying to figure out is how to specify a file path as a variable when I run the script?
update [$Db_name].[dbo].[$BatchTable]
set [$Db_name].[dbo].[$BatchTable].Wave = 'Wave1.1'
from [$Db_name].[dbo].[$BatchTable]
inner join OPENROWSET(BULK 'FilePath\file.csv',
FORMATFILE= 'E:\import.xml') AS a
on ([$Db_name].[dbo].[$BatchTable].Name= a.Name) and
([$Db_name].[dbo].[$BatchTable].Domain = a.Domain)
The 'FilePath\file.csv' is the file path I need to define as a variable so that my code would instead look like this:
inner join OPENROWSET(BULK '$INPUTFILEPATH',
FORMATFILE= 'E:\import.xml') AS a
Any help or potentially better methods to accomplish this would help very much.
From the command like I want to be able to run the script like this:
CMD: updatescript.ps1 $INPUTFILEPATH = C:\Documents\myfile.csv
Again, I'm not sure this is the best way to go about this?
You're nearly there.
You will need to add a parameter block at the very start of your script e.g.
Param(
[Parameter(Mandatory=$true)]
[ValidateScript({Test-Path $_ -PathType 'leaf'})]
[string] $InputFilePath
)
This creates a mandatory (not optional) string parameter, called InputFilePath, and the ValidateScript is code used to validate the parameter, in this case checking the file exists using the Test-Path cmdlet and pathtype of leaf (if checking existence of a directory use 'container').
When running your script use the syntax below:
updatescript.ps1 -INPUTFILEPATH "C:\Documents\myfile.csv"
and in the script use the variable as the path exactly as in your question:
inner join OPENROWSET(BULK '$INPUTFILEPATH',
FORMATFILE= 'E:\import.xml') AS a
NOTE: in powershell when using parameters when running a script you only need to use the least amount of characters that uniquely identify that parameter from all the others in your param block - in this case -I works just as well as -InputFilePath.
You can pass command line parameters to the powershell script using param.
Example:
param(
[string]$INPUTFILEPATH
)
And then call the script as follows:
updatescript.ps1 -INPUTFILEPATH C:\Documents\myfile.csv
More details about cmd line parameters can be found here
How can I find out (with Windows a batch command), if, for example, a variable starts with ABC?
I know that I can search for variables if I know the whole content (if "%variable%"=="abc"), but I want that it only looks after the beginning.
I also need it to find out where the batch file is located, so if there is a other command that reveals the file's location, please let me know.
Use the variable substring syntax:
IF "%variable:~0,3%"=="ABC" [...]
If you need the path to the batch file without the batch file name, you can use the variable:
%~dp0
Syntax for this is explained in the help for the for command, although this variable syntax extends beyond just the for command syntax.
to find batch file location use %0 (gives full patch to current batch file) or %CD% variable which gives local directory
I was originally trying to run an executable (tftpd32.exe) from Expect with the following command, but for some unknown reason it would hanged the entire script:
exec c:/tftpd32.351/tftpd32.exe
So, decided to call a batch file that will start the executable.
I tried to call the batch file with the following command, but get an error message stating windows cannot find the file.
exec c:/tftpd32.351/start_tftp.bat
I also tried the following, but it does not start the executable:
spwan cmd.exe /c c:/tftpd32.351/start_tftp.bat
The batch file contains this and it run ok when I double click on it:
start tftpd32.exe
Any help would be very much appreciated.
Thanks
The right way to run that program from Tcl is to do:
set tftpd "c:/tftpd32.351/tftpd32.exe"
exec {*}[auto_execok start] "" [file nativename $tftpd]
Note that you should always have that extra empty argument when using start (due to the weird way that start works; it has an optional string in quotes that specifies the window title to create, but it tends to misinterpret the first quoted string as that even if that leaves it with no mandatory arguments) and you need to use the native system name of the executable to run, hence the file nativename.
If you've got an older version of Tcl inside your expect program (8.4 or before) you'd do this instead:
set tftpd "c:/tftpd32.351/tftpd32.exe"
eval exec [auto_execok start] [list "" [file nativename $tftpd]]
The list command in that weird eval exec construction adds some necessary quoting that you'd have trouble generating otherwise. Use it exactly as above or you'll get very strange errors. (Or upgrade to something where you don't need nearly as much code gymnastics; the {*} syntax was added for a good reason!)
I am trying to set up some path using environment variable.
I added an environment variable "MAVEN_HOME" with the value "C:\maven".
Then in the path I added "%MAVEN_HOME%\bin;...rest".
When I type "echo $MAVEN_HOME%" I get the correct "C:\maven" printed on the screen.
But when I type "mvn" which is a batch file in the "bin" directory, it can't find it.
So, I manually added the entire path in PATH.
"C:\maven\bin;...rest"
and it was able to find "mvn" and execute it.
Could someone help me what I did wrong?
Check if there is a space character between the previous path and the next:
Incorrect:
c:\path1; c:\Maven\bin\; c:\path2\
Correct:
c:\path1;c:\Maven\bin\;c:\path2\
I had exactly the same problem, to solve it, you can do one of two things:
Put all variables in System Variables instead of User and add the ones you want to PATH
Or
Put all variables in User Variables, and create or edit the PATH variables in User Variable, not In System. The Path variables in System don't expand the User Variables.
If the above are all correct, but the problem is still present, you need to check the system Registry, in HKEY_CURRENT_USER\Environment, to make sure the "PATH" key type is REG_EXPAND_SZ (not REG_SZ).
My issue turned out to be embarrassingly simple:
Restart command prompt and the new variables should update
Things like having %PATH% or spaces between items in your path will break it. Be warned.
Yes, windows paths that include spaces will cause errors. For example an application added this to the front of the system %PATH% variable definition:
C:\Program Files (x86)\WebEx\Productivity Tools;C:\Sybase\IQ-16_0\Bin64;
which caused all of the paths in %PATH% to not be set in the cmd window.
My solution is to demarcate the extended path variable in double quotes where needed:
"C:\Program Files (x86)\WebEx\Productivity Tools";C:\Sybase\IQ-16_0\Bin64;
The spaces are therefore ignored and the full path variable is parsed properly.
%M2% and %JAVA_HOME% need to be added to a PATH variable in the USER variables, not the SYSTEM variables.
If there is any error at all in the PATH windows will silently disregard it. Things like having %PATH% or spaces between items in your path will break it. Be warned
Also worth making sure you're using the command prompt as an administrator - the system lock on my work machine meant that the standard cmd just reported mvn could not be found when typing
mvn --version
To use click 'start > all programs > accessories', right-click on 'command prompt' and select 'run as administrator'.
To address this problem, I have used setx command which try to set user level variables.
I used below...
setx JAVA_HOME "C:\Program Files\Java\jdk1.8.0_92"
setx PATH %JAVA_HOME%\bin
NOTE: Windows try to append provided variable value to existing variable value. So no need to give extra %PATH%... something like %JAVA_HOME%\bin;%PATH%
If the PATH value would be too long after your user's PATH variable has been concatenated onto the environment PATH variable, Windows will silently fail to concatenate the user PATH variable.
This can easily happen after new software is installed and adds something to PATH, thereby breaking existing installed software. Windows fail!
The best fix is to edit one of the PATH variables in the Control Panel and remove entries you don't need. Then open a new CMD window and see if all entries are shown in "echo %PATH%".
I had this problem in Windows 10 and it seemed to be solved after I closed "explorer.exe" in the Task Manager.
In my Windows 7.
// not working for me
D:\php\php-7.2.6-nts\php.exe
// works fine
D:\php\php-7.2.6-nts
I had the same problem, I fixed it by removing PATHEXT from user variable. It must only exist in System variable with .COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC
Also remove the variable from user to system and only include that path on user variable
Copy the value of path to notepad and check if this corresponds with the echo %path% in terminal window and make changes if needed. Then delete the old path value and paste the notepad value back in.
I assume some invisible character entered there by some installation corrupted the path value.
Make sure both your System and User paths are set correctly.