Question about append to a file

Archive: Question about append to a file

Ben_101
22nd July 2008 13:12 UTC

Question about append to a file
Hello all,
I am completely new in scripting an installer, and I would to open a file to write 1 line at the end of it.

I have created a function:
Function writeLogFile ;
ClearErrors
FileOpen $0 $INSTDIR\file.dat a
IfErrors done
FileWrite $0 "new text"
FileClose $0
done:
FunctionEnd

But this write always the line on the first line of the file.
Can someone help me on this ?
Thanks !

pospec
22nd July 2008 13:15 UTC

Try FileSeek after opening the file: http://nsis.sourceforge.net/Reading_...iting_in_files

LoRd_MuldeR
22nd July 2008 13:16 UTC

Re: Question about append to a file

Originally posted by Ben_101
Hello all,
I am completely new in scripting an installer, and I would to open a file to write 1 line at the end of it.

I have created a function:
Function writeLogFile ;
ClearErrors
FileOpen $0 $INSTDIR\file.dat a
IfErrors done
FileWrite $0 "new text"
FileClose $0
done:
FunctionEnd

But this write always the line on the first line of the file.
Can someone help me on this ?
Thanks !

Do it like this ;)

Function writeLogFile
  ClearErrors
  FileOpen $0 $INSTDIR\file.dat a
  IfErrors done
  FileSeek $0 0 END          ; <-- Set pointer to the end of the file
  FileWrite $0 "new text"
  FileWrite $0 "$\r$\n"      ; <-- Add carriage return
  FileClose $0
  done:
FunctionEnd

pospec was faster :D

Ben_101
23rd July 2008 13:17 UTC

This is working fine now.
Thank you for your help !