sancho1980 wrote:
> hi
> would someone please explain to me this typedef in line 01321 of
> appendix b:
>
> typedef void (*tmr_func_t)(struct timer *tp);
>
> i figure its a void datatype, but i don't know what the
> (*tmr_func_t)(struct timer *tp); is supposed to say...the book also
> mentions how the timer struct makes use of tmr_func_t but to me this
> definition doesnt make sense as it doesnt conform to my understnading
> of a typedef as
>
> "typedef existing_type new_type_name"

The typedef reads as "tmr_func_t is a user defined type name for a
pointer to a function (returning void) that takes a pointer to a timer
structure as an argument."

HTH

--
Lew

sancho1980 wrote:

> typedef void (*tmr_func_t)(struct timer *tp);

The new type tmr_func_t is defined as the pointer to a function
returning nothing (void) and expecting a pointer to a 'struct timer'

> i figure its a void datatype, but i don't know what the
> (*tmr_func_t)(struct timer *tp); is supposed to say...the book also
> mentions how the timer struct makes use of tmr_func_t but to me this
> definition doesnt make sense as it doesnt conform to my understnading
> of a typedef as
>
> "typedef existing_type new_type_name"

Read it this way (as you put it):

typedef void (*)(struct timer *) tmr_func_t;
[ -- existing_type -- ] [ new type ]

Ciao
Giovanni
--
A computer is like an air conditioner,
it stops working when you open Windows.
Registered Linux user #337974 < http://giovanni.homelinux.net/ >