What does this function do?

[Anil Gupte]

I am trying to learn C++ and one sample written by someone for me contains
this:

void DecryptStream(B YTE* buf, ULONG size)
{
for (ULONG i=0; i<size; i++)
{
buf[i] ^= 1;
}
}

Can some one tell me what this is doing? Especially ^ - is that an XOR?

Thanx,
--
Anil Gupte

https://www.keeninc.net

www.icinema.com

[Cholo Lennon]

Re: What does this function do?

"Anil Gupte" <anil-list@icinema.co mwrote in message
news:ObtdotVQIH A.4880@TK2MSFTN GP03.phx.gbl...

I am trying to learn C++ and one sample written by someone for me contains
this:
>
void DecryptStream(B YTE* buf, ULONG size)
{
for (ULONG i=0; i<size; i++)
{
buf[i] ^= 1;
}
}
>
Can some one tell me what this is doing? Especially ^ - is that an XOR?
>

Yes, ^ is the C/C++ XOR operator, so the function 'decrypt' the stream of
bytes (but can be used to 'crypt' the data too).

Regards


--
Cholo Lennon
Bs.As.
ARG

[Ben Voigt [C++ MVP]]

Re: What does this function do?


"Anil Gupte" <anil-list@icinema.co mwrote in message
news:ObtdotVQIH A.4880@TK2MSFTN GP03.phx.gbl...

>I am trying to learn C++ and one sample written by someone for me contains
>this:
>
void DecryptStream(B YTE* buf, ULONG size)
{
for (ULONG i=0; i<size; i++)
{
buf[i] ^= 1;
}
}
>
Can some one tell me what this is doing? Especially ^ - is that an XOR?

As Cholo already told you, yes that's XOR.

It flips the least significant bit of each of <sizebytes starting at
<buf>, which should not be called "decryption ".

>
Thanx,
--
Anil Gupte

https://www.keeninc.net

www.icinema.com
>

[Anil Gupte]

Re: What does this function do?

Thanx for the info! Ben and Cholo.

--
Anil Gupte

https://www.keeninc.net

www.icinema.com

"Ben Voigt [C++ MVP]" <rbv@nospam.nos pamwrote in message
news:OiiemBcQIH A.5692@TK2MSFTN GP04.phx.gbl...

>
"Anil Gupte" <anil-list@icinema.co mwrote in message
news:ObtdotVQIH A.4880@TK2MSFTN GP03.phx.gbl...

>>I am trying to learn C++ and one sample written by someone for me contains
>>this:
>>
>void DecryptStream(B YTE* buf, ULONG size)
>{
> for (ULONG i=0; i<size; i++)
> {
> buf[i] ^= 1;
> }
>}
>>
>Can some one tell me what this is doing? Especially ^ - is that an XOR?

>
As Cholo already told you, yes that's XOR.
>
It flips the least significant bit of each of <sizebytes starting at
<buf>, which should not be called "decryption ".
>

>>
>Thanx,
>--
>Anil Gupte
>www.keeninc.net
>www.icinema.com
>>

>
>