LineFind : discovering an existing line that starts with a dedecated string: HOW?

[within]

Hi there,

I'd wish to modify a text file only if a dedicated string in this file is NOT written there already.

I'd like to compare each lines in a file to check if this line starts with a dedicated string, let's say a line can be:
'user is defined as blabla'

and string to use for check is 'user'.

so, as soon as, within a file, the script does find a line that starts with 'user' it will stop and goto another part of the script that will do 'action 1', or if it does not find any line that starts with the string 'user', it will do 'action 2'.

I thought I could use ${LineFind} "[File1]" "[File2|/NUL]" "[LineNumbers]" "Function"

but I have some difficulties for the 'Function', and compare process...

[MSG]

ClearErrors
FileOpen $0 $INSTDIR\file.dat r
IfErrors notfound
loop:
FileRead $0 $1
IfErrors goto notfound
StrCpy $2 $1 4
StrCmp $2 "user" bingo
goto loop
end:
FileClose $0
notfound:
MessageBox MB_OK "Not found."
goto done
bingo:
MessageBox MB_OK "Found."
goto done
done:

[within]

Thanks very much MSG for your code!

I'll test it tomorrow.

[MSG]

Oh, and you should always FileClose. So you could move that to below the done label, I guess.

[within]

Indeed, the FileClose was not at the best positon. I had to add anothyer one too, depending on conditions.

here is my code:

code:
Section SecSetServ



	; check if Environement variable is already defined

	ClearErrors

	FileOpen $0 "$WINDIR\system32\drivers\etc\services" a		; Open mode is  "a" for append

	IfErrors notfound

	loop:

	FileRead $0 $1

	IfErrors notfound

	StrCpy $2 $1 4

	StrCmp $2 "user" found

	Goto loop

	notfound:

	Goto done

	found:

	Goto finished

	done: 

	FileClose $0

  ; Modify system files ("service" files)

  Call SysFiles						

  Goto veryend



  finished:

  FileClose $0

  ${GetTime} "" "L" $0 $1 $2 $3 $4 $5 $6

  Push "$2/$1/$0 $4:$5:$6 [INSTALL] - Services ports ALREADY defined.$\r$\n $\r$\n" ;text to write to file 

  Push "$INSTDIR\_setup.log" ;file to write to 

  Call WriteToFile



  veryend:

  

SectionEnd

[within]

tested with success!

Thanks MSG

[MSG]

Next up: Using LogicLib instead of Strcmp and goto's.

[within]

I didn't know about this one; looks cool. Thanks for the tip!