Help with length of buffer

For the third parameter of the recv() function MSDN says:

"The length, in bytes, of the buffer pointed to by the buf parameter."

Does it mean the size of the char[] variable or the length of the data in it?

For example: "Hello world" is 12 characters long (with the '\0') which would be 1 byte because you can put 256 characters in one byte.

If its the size of the variable its also enough 1 byte ( char[1] ) for the same reason i guess.

Im a bit confused why everybody's using big numbers like 32, 64 etc...

Code:

---


char  buf[1];

recv(s, buf, 1, 0);

---

>> Does it mean the size of the char[] variable or the length of the data in it?

The size of the buffer itself (the length of the text in the buffer doesn't really matter, anyway, since it's just going to be overwritten).

>> For example: "Hello world" is 12 characters long (with the '\0') which would be 1 byte because you can put 256 characters in one byte.

Not exactly. An 8 bit byte can hold *one* of 256 possible values. Or *eight* of 2 possible values (if you packed each value onto a single bit). You can do a better than that with certain compression schemes (such as arithmetic encoding), but that's beyond the scope of this post (see: information theory). The point is, using standard ASCII coding, 12 characters == 12 bytes.

Quote:

---

Originally Posted by Ducky

Im a bit confused why everybody's using big numbers like 32, 64 etc...

---

Likely it's measured in bits.
32 bits = 4 bytes.
64 bits = 8 bytes.
And so on. Common in the computer world.

Thank you Sebastiani and Elisia for your explanation! :)

Have a good day!