Replace one ASCII char in a binary file?

[emendelson]

I've been studying various posts here, and studying the help file, and this problem is still beyond me.

For a script I'm writing, I want to replace one character in a binary file; the character I want to replace will be an alphabetical character, and I will want to replace it with another alphabetical character. It's always in the same position in the file (51h). I do not need to read the file to learn what the original character is; I only need to insert the replacement character, for example "K" or "V" or whatever letter happens to be needed.

(Details: the file is a macro file created by the old WordPerfect for DOS 5.1 program; I'm trying to insert the current drive letter into the macro, which will be used by WordPerfect.)

I think I need to use FileOpen, FileSetPos, and FileWrite, but I can't see exactly how to do this. Any advice or sample code would be very welcome. Thank you.

Edited October 8, 2010 by Edward Mendelson

[emendelson]

Figured out for myself - sorry to waste bandwidth:

$m = FileOpen($myfile, 17)
FileSetPos($m, 81, $FILE_BEGIN)
FileWrite($m, "X")
FileClose($m)