querry regarding function pointer

[Lalatendu Das]

hi
Please someone give a real time implimentation of a function pointer.
where exactly we need a function pointer very much . if it is in terms
of code i will be happy enough .
thanks in advance

[pemo]

Lalatendu Das wrote:

hi
Please someone give a real time implimentation of a function pointer.
where exactly we need a function pointer very much . if it is in terms
of code i will be happy enough .
thanks in advance

#include <stdio.h>
#include <signal.h>
void sigterm_handler (int sig)
{
printf("Handlin g signal %d", sig);
}
int main(void)
{
signal(SIGTERM, sigterm_handler );

raise(SIGTERM);

return 0;
}
--
==============
Not a pedant
==============

[Vladimir S. Oka]

Lalatendu Das wrote:

Please someone give a real time implimentation of a function pointer.
I guess you mean "real world"...
where exactly we need a function pointer very much.
It really depends on your application. Simulating polymorphism is one.
if it is in terms of code i will be happy enough.

#include <math.h>
#include <stdio.h>

#define PI 3.14159

double (*trig)(double) ;

int main(void)
{
trig = sin;
printf("sin(PI) = %f\n", (*trig)(PI/2.0));

trig = cos;
printf("cos(PI) = %f\n", (*trig)(PI/2.0));

return 0;
}

--
BR, Vladimir

[Richard Heathfield]

Lalatendu Das said:

hi
Please someone give a real time implimentation of a function pointer.
where exactly we need a function pointer very much . if it is in terms
of code i will be happy enough .

You can find good examples on page 118 of "The C Programming Language", 2nd
edition, by Kernighan and Ritchie, or on pages 146-147 of "C - A Reference
Manual", 4th edition, by Harbison and Steele.
--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[Lalatendu Das]

thanks for all your answers .They are really good. But specifically
from the point veiw of protocol stack developement is there any
instance which make use of pointer very needy andbest as well

[osmium]

Yes, of course.

[Vladimir S. Oka]

On Thursday 16 March 2006 15:45, osmium opined (in
<47************ @individual.net >):

Yes, of course.

But if I tell him, I'll have to kill him.

--
BR, Vladimir

It's amazing how much "mature wisdom" resembles being too tired.

[Vladimir S. Oka]

On Thursday 16 March 2006 15:24, Lalatendu Das opined (in
<11************ **********@j33g 2000cwa.googleg roups.com>):

thanks for all your answers .They are really good. But specifically
from the point veiw of protocol stack developement is there any
instance which make use of pointer very needy andbest as well

Quote context, otherwise your posts make little sense. For example, it's
an accident that I know you mean "function pointers" not just any
pointers. Read and heed: <http://cfaj.freeshell. org/google/>. This
one <http://clc-wiki.net/wiki/Introduction_to _comp.lang.c> is also
useful.

Back to your question: yes, there is a perfectly good place for function
pointers in protocol stack development.

<OT>
For example: programming a sequence of tasks for the DSP to perform in
lower parts of protocol stack of a mobile phone.
</OT>
--
BR, Vladimir

Trust in Allah, but tie your camel.
-- Arabian proverb