[RTEMS Project] #4271: Add common malloc family extension method malloc_usable_size()

[RTEMS trac]

#4271: Add common malloc family extension method malloc_usable_size()
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  Reporter:  Joel Sherrill  |      Owner:  (none)
      Type:  enhancement    |     Status:  new
  Priority:  normal         |  Milestone:  Indefinite
 Component:  posix          |    Version:  6
  Severity:  normal         |   Keywords:  small, tasks
Blocked By:                 |   Blocking:
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 RTEMS already has this functionality so it should not be hard to implement
 this.

 https://man7.org/linux/man-pages/man3/malloc_usable_size.3.html
 https://www.freebsd.org/cgi/man.cgi?query=malloc_usable_size

 The prototype would need to be added to the appropriate newlib header file
 with the same guard as Linux and FreeBSD.

 The method would need to be fully tested.

 The method would need to be documented.

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Ticket URL: <http://devel.rtems.org/ticket/4271>
RTEMS Project <http://www.rtems.org/>
RTEMS Project