Difference between Exec and nsExec

[mwiseman]

Hello,

I'm trying to run an executable using nsExec. The run always ends in an error that indicates an executable-related error.

nsExec::ExecToLog '"myapp.exe"'

I can run the same executable using Exec without a problem.

Exec '"myapp.exe"'

Thinking that the environment may be the issue, I've tried:

nsExec::ExecToLog '<path_to_cmd.exe> /C "myapp.exe"'

to no avail. This problem seems to point to differences in how nsExec and Exec work but I don't know what they are. Any ideas?

Thanks,

Mike

[flizebogen]

nsexec was written for command line apps. With nsexec::ExecToLog you can capture the outpu of the app and display it in the result window.
As far as i know it doesn't support live output as used by programs like rar.

[mwiseman]

myapp.exe is a command line app:

c:\>myapp.exe

Writes to cmd.exe window and terminates.

[Afrow UK]

Something like this should work:

code:


!define LogFile "$INSTDIR\myapp_dump.txt"

Push $R0

 ReadEnvStr $R0 COMSPEC

 nsExec::Exec '$R0 /C "$INSTDIR\myapp.exe" > "${LogFile}"'

 FileOpen $R0 "${LogFile}" r

  LoopRead:

   ClearErrors

   FileRead $R0 $R1

    IfErrors LoopDone

    Push $R1

     Call TrimNewLines

    Pop $R1

   DetailPrint $R1

   Goto LoopRead

  LoopDone:

 FileClose $R0

Pop $R0

SetDetailsPrint none

 Delete "${LogFile}"

SetDetailsPrint both

That would be another method of capturing the output.
Note that nsExec::Exec will run your application and hide it completely from the user (so the user will not see a command-prompt window.)

-Stu

[mwiseman]

Thanks for the script but this doesn't really answer my question. I'm not looking for more error output from the nsExec run. The 'nsExec::ExecToLog' does write the errors to the result window. My question is: why would *any* command line program run to completion using:

Exec '"myapp.exe"'

but fail using:

nsExec::ExecToLog '"myapp.exe"'


I'll be more specific now: the app I'm trying to run is Microsoft's Baseline Security Analyzer utility: mbsacli.exe. The error I get seem to be network-related - 'no computer were found'.

[Afrow UK]

Well, as nsExec doesn't execute your program through COMSPEC then perhaps that's why it is failing. Maybe you have to run it through COMSPEC for it to work?

-Stu

[Takhir]

Windows MS DOS (console) window is a bit more complex then a process with stdin and stdout only. Simple console applications work fine with nsExec, but some apps require more - terminal emulation or something else (like telnet does). This may be a reason, Exec creates full MS DOS console window, but nsExec simply redirects IO to pipes. You can also try ExecWait with SW_HIDE.

[Comm@nder21]

You can also try ExecWait with SW_HIDE.

does execwait support window state parameters like SW_HIDE ?

from the nsis docs:

command [user_var(exit code)]

as i need to run a cmd-program in a loop, i need to get the installer wait until it has finished, but also to execute it in the backround without popping up the shell window everytime.

does nsExec::Exec do this, or is it possible to use SW_HIDE with ExecWait?

[Takhir]

Yes, you are right, I probably had in mind ExecShell. IMHO one of DOS-exec plug-ins is a good decision in your situation.

[kichik]

It always complains about being unable to create a scan object for me. Can you attach a complete example for which you get the error you're talking about?