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Re: correct way to create dynamically function pointers

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John Bode <jfbode1029@gmail.com> writes:
<snip>
> Let's start from the beginning.  If you want to dynamically allocate an 
> N-element array of any type T, you'd write:
>
>     T *p = malloc( N * sizeof *p );
>
> or
>
>    T *p = NULL;
>    ...
>    p = malloc( N * sizeof *p ); 
>
> After this, each p[i] contains a value of type T.

s/contains/can contain/

After the malloc call each p[i] has indeterminate value.  That value
can't be used in any way.  All you can do is use p[i] as somewhere to
put a value of type T

> Now, let's replace T with a pointer type, P * - you want to allocate an
> N-element array of *pointers* to P:
>
>     P **p = malloc( N * sizeof *p );
>
> or
>
>    P **p = NULL;
>    ...
>    p = malloc( N * sizeof *p );
>
> After this, each p[i] contains a value of type P *,

Same here.  True only once you've put something determinate in p[i].

<snip>
-- 
Ben.

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Thread

correct way to create dynamically function pointers Hello World <acidlategamer@gmail.com> - 2017-04-11 10:20 -0700
  Re: correct way to create dynamically function pointers scott@slp53.sl.home (Scott Lurndal) - 2017-04-11 17:34 +0000
    Re: correct way to create dynamically function pointers Hello World <acidlategamer@gmail.com> - 2017-04-11 10:42 -0700
      Re: correct way to create dynamically function pointers scott@slp53.sl.home (Scott Lurndal) - 2017-04-11 17:48 +0000
        Re: correct way to create dynamically function pointers Hello World <acidlategamer@gmail.com> - 2017-04-11 10:55 -0700
      Re: correct way to create dynamically function pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-11 19:06 +0100
      Re: correct way to create dynamically function pointers "James R. Kuyper" <jameskuyper@verizon.net> - 2017-04-11 14:23 -0400
    Re: correct way to create dynamically function pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-11 19:05 +0100
    Re: correct way to create dynamically function pointers "James R. Kuyper" <jameskuyper@verizon.net> - 2017-04-11 14:11 -0400
      Re: correct way to create dynamically function pointers Richard Heathfield <rjh@cpax.org.uk> - 2017-04-12 08:27 +0100
        Re: correct way to create dynamically function pointers "James R. Kuyper" <jameskuyper@verizon.net> - 2017-04-12 13:31 -0400
          Re: correct way to create dynamically function pointers Richard Heathfield <rjh@cpax.org.uk> - 2017-04-12 23:05 +0100
  Re: correct way to create dynamically function pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-11 19:03 +0100
  Re: correct way to create dynamically function pointers "James R. Kuyper" <jameskuyper@verizon.net> - 2017-04-11 14:05 -0400
    Re: correct way to create dynamically function pointers Jorgen Grahn <grahn+nntp@snipabacken.se> - 2017-04-15 10:19 +0000
      Re: correct way to create dynamically function pointers asetofsymbols@gmail.com - 2017-04-15 05:09 -0700
  Re: correct way to create dynamically function pointers Barry Schwarz <schwarzb@dqel.com> - 2017-04-11 15:13 -0700
    Re: correct way to create dynamically function pointers Richard Heathfield <rjh@cpax.org.uk> - 2017-04-12 08:28 +0100
  Re: correct way to create dynamically function pointers Richard Heathfield <rjh@cpax.org.uk> - 2017-04-12 08:19 +0100
    Re: correct way to create dynamically function pointers Spiros Bousbouras <spibou@gmail.com> - 2017-04-12 21:17 +0000
      Re: correct way to create dynamically function pointers Richard Heathfield <rjh@cpax.org.uk> - 2017-04-12 23:11 +0100
        Re: correct way to create dynamically function pointers Keith Thompson <kst-u@mib.org> - 2017-04-12 16:36 -0700
  Re: correct way to create dynamically function pointers John Bode <jfbode1029@gmail.com> - 2017-04-12 10:04 -0700
    Re: correct way to create dynamically function pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-04-12 19:28 +0100
    Re: correct way to create dynamically function pointers Tim Rentsch <txr@alumni.caltech.edu> - 2017-04-17 05:50 -0700

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