What the heck is up with BINARY file i/o?

What the heck is up with BINARY file i/o? - Printable Version

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What the heck is up with BINARY file i/o? - Zack - 04-12-2007

I want to make a program, very basic, that will XOR the first byte in a file with a code, and replace that byte with the new character.

Code:
dim as string infile

input "infile: ",infile

dim as ubyte code

input "code:",code

open infile for binary as #1

dim as ubyte temp,c

get #1,1,temp

c=temp xor code

put #1,1,temp xor code

close #1

It simply doesn't work. It ruins the file, adding extra characters and changing the size of the file. Any insight?

What the heck is up with BINARY file i/o? - DrV - 04-12-2007

The expression 'temp xor code' that you are using in the PUT statement is evaluated in a full 32-bit integer. Cast to a UByte or do it in a temporary variable to get the right results.

What the heck is up with BINARY file i/o? - Zack - 04-12-2007

Thanks, it works. Funny, I tried that with the c=... line, but I forgot to use c instead in the PUT statement.