How to prevent running same script more than once?

[TheInsider]

I need my script to run as 'single instance' (Meaning it will end if the same script is already running), but my search for a simple way is coming up empty.

Autohotkey has the #SingleInstance directive, which makes it a simple one-line deal.

I know I can do things such as creating/checking for a dummy file, etc. Just wondered if there is an established method.

[Joe Caverly]

Eros describes how to do this using a MUTEX.

Ref: https://www.thinbasic.com/community/...e-copy-running

Joe

[Joe Caverly]

Example source code;

dim Mutex_Handle as dword
dim Mutex_Name as string = "UniqueMutexName"


Mutex_Handle = APP_MutexCreate(Mutex_Name)


if Mutex_Handle = 0 then
    msgbox 0, "Another instance of the script is already running.", %MB_ICONERROR
    stop
else
    msgbox 0, "Script is running. Mutex created successfully.", %MB_ICONINFORMATION
end if

'---At the end close the mutex handle to release it for new script execution
APP_MutexClose(Mutex_Handle)

Joe

[TheInsider]

Thank you Joe. That is exactly what I was looking for.

I did search the forums, sample programs, Google, etc. I recall seeing 'Mutex' in the search, but since I didn't understand what I was looking at, I passed it by.
It's quite simple to use now that I see your example code.

PS. For future readers, you might want to edit that typo (dworddim) in the first line.

[Joe Caverly]

PS. For future readers, you might want to edit that typo (dworddim) in the first line.

Code has been fixed, thankyou for catching that.

For whatever reason, it pasted without a LF/CR in that line when copying to the forum.

Joe

[Joe Caverly]

There was no need to scoure the internet,
as thinbasic includes a sample called MUTEX.tbasic

 Volume in drive E is New Volume   Serial number is 2c1e:6e61
 Directory of  E:\thinBasic\SampleScripts\General\MUTEX.tbasic


2019-02-06   7:12           1,032  MUTEX.tbasic
               1,032 bytes in 1 file and 0 dirs    4,096 bytes allocated
   1,335,186,173,952 bytes free

dim hMutex      as dword
dim Mutex_Name  as string = "AVeryUniqueStringToNameMutex"


'---Better if MutexName has script name inside so it will be specific to this script
Mutex_Name += app_scriptname


hMutex = APP_MutexCreate(Mutex_Name)


if hMutex = 0 then
  msgbox 0, _
            "I was not able to create a Mutex named: " & Mutex_Name & $crlf & _
            "This means that another instance of the same script is already running" & $crlf & _
            "or you have not enough user authorization to create a Mutex." & $crlf & _
            "In any case script execution is aborted. Sorry", %MB_ICONERROR
  stop
else
  msgbox 0, _
            "I was able to create a Mutex named: " & Mutex_Name & $crlf & _
            "Mutex handle is " & hMutex & "" & $crlf & _
            "Script will continue. Perfect", %MB_ICONINFORMATION


end if


'...
'------
'---Here code for script ...
'---
'...


'---At the end close the mutex handle to release it for new script execution
APP_MutexClose(hMutex)

Now we know!

Joe

[ErosOlmi]

Hi Joe, thanks a lot for supporting TheInsider !
All perfect.
Appreciated.