NSIS Find all .txt files

Question

I currently have a check to find all text files in $INSTDIR, shown below.

However, there could potentially be subdirectories, such as $INSTDIR\mySub, which contains additional .txt files. Is there a way to keep a similar loop structure but search all subdirectories as well?

FindFirst $R0 $R1 "$INSTDIR\*.txt"
IfErrors ExitInstaller 0
LoopIt:
  Messagebox MB_OK "Do some processing on $R1"
  FindNext $R0 $R1
  IfErrors 0 LoopIt

Answer 1

Function ProcessTextFiles
Exch $0
Push $1
Push $2
FindFirst $1 $2 "$0\*.txt"
loop:
    IfErrors end
    DetailPrint 'Found "$0\$2"'
    FindNext $1 $2
    goto loop
end:
FindClose $1
FindFirst $1 $2 "$0\*.*"
dirloop:
    IfErrors dirend 
    IfFileExists "$0\$2\*.*" 0 dirnext
    StrCmp $2 "." dirnext
    StrCmp $2 ".." dirnext
    Push "$0\$2"
    call ${__FUNCTION__}
dirnext:
    FindNext $1 $2
    goto dirloop
dirend:
FindClose $1
Pop $2
Pop $1
Pop $0
FunctionEnd

section
push "$InstDir"
call ProcessTextFiles
sectionend

Answer 2

Try to use the Locate function instead -- it could be much better solution. You can write options to find with (or without) subdirectories, define mask and so on. See http://nsis.sourceforge.net/Locate for doc and examples.