help: %comspec% - Forums

.data

programname db "%COMSPEC%",0
progcmdline db "/C START C:\WINNT\NOTEPAD.EXE"

processInfo PROCESS_INFORMATION <>
startInfo STARTUPINFO <>

.code

start:

invoke CreateProcess,programname,progcmdline,NULL,NULL,FALSE,\
NORMAL_PRIORITY_CLASS,\
NULL,NULL,ADDR startInfo,ADDR processInfo

invoke ExitProcess,NULL

end start
....
after compiling and trying to run the EXE it crashes :(, it works perfect if i don't use %comspec% to start notepad, but %comspec% is the way i want to go.

How do i fix this (code would be preferred!)? im using MASM v6, & W2k.

Thanks in advance, help is always heavily appreciated!

Posted on 2001-11-24 07:40:55 by ashtr3jd

help: %comspec%

Two things:
1) I think you need "ADDR programname" and "ADDR progcmdline" as passing a string is usually done by reference (this could be one cause of your crash).

2) The string "%COMSPEC%" is probably not evaluated, it is used directly (ie. As a literal string).
Try the following:



.data

env         db "COMSPEC",0

progcmdline db "/C START C:\WINNT\NOTEPAD.EXE", 0

buffer      db 2048 dup (0)



processInfo PROCESS_INFORMATION <> 

startInfo STARTUPINFO <> 



.code

start:

    invoke GetEnvironmentVariable, ADDR env, ADDR buffer, SIZEOF(buffer)

    invoke CreateProcess, ADDR buffer, ADDR progcmdline, NULL, NULL, \

                          FALSE, NORMAL_PRIORITY_CLASS, NULL,NULL, \

                          ADDR startInfo,ADDR processInfo 



    invoke ExitProcess, eax

end start

The code may not work exactly, I'm working off the top of my head, but its about right...

Mirno

Posted on 2001-11-24 11:37:40 by Mirno

Thanks! =))

you 0wn Mirno :alright:

worked perfectly just changed
invoke GetEnvironmentVariable, ADDR env, ADDR buffer, SIZEOF (buffer)

to --> invoke GetEnvironmentVariable, ADDR env, ADDR buffer, SIZEOF buffer

i guess even the best can miss things (like ADDR ;) )

Thanks again :)

Posted on 2001-11-24 12:59:38 by ashtr3jd

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