Question of function argument

[gigal]

Could someone explain how the function is defined with argument like this?

bool select(long lEvent = FD_READ | FD_WRITE | FD_OOB | FD_ACCEPT |
FD_CONNECT | FD_CLOSE );

Thank you very much!

[John Harrison]

"gigal" <gi*******@168.com> wrote in message
news:tZ********************@bgtnsc05-news.ops.worldnet.att.net...

Could someone explain how the function is defined with argument like this?

bool select(long lEvent = FD_READ | FD_WRITE | FD_OOB | FD_ACCEPT |
FD_CONNECT | FD_CLOSE );

Thank you very much!

What's to explain? It's a function called select, it returns a bool, it has
a single parameter of type long.

Maybe what's confusing you is that the parameter has a default value, if the
caller of the function doesn't supply an argument then a default value of
FD_READ | FD_WRITE | FD_OOB | FD_ACCEPT | FD_CONNECT | FD_CLOSE will be used
instead.

Does that help? If not explain a little more about what exactly you don't
understand.

john

[Corne' Cornelius]

Hi,

That means that it's a function called select, returns bool, and has an
argument called lEvent of type long, with a default value of all those
FD_* (probably #defines or enums) bitwise OR'd together
gigal wrote:

Could someone explain how the function is defined with argument like this?

bool select(long lEvent = FD_READ | FD_WRITE | FD_OOB | FD_ACCEPT |
FD_CONNECT | FD_CLOSE );

Thank you very much!

[Jeff Schwab]

Corne' Cornelius wrote:

Hi,

That means that it's a function called select, returns bool, and has an
argument called lEvent of type long, with a default value of all those
FD_* (probably #defines or enums)
Or long const's.
bitwise OR'd together
gigal wrote:

Could someone explain how the function is defined with argument like
this?

bool select(long lEvent = FD_READ | FD_WRITE | FD_OOB | FD_ACCEPT |
FD_CONNECT | FD_CLOSE );

Thank you very much!