4.1. Malloc subsystem

A process can dynamically allocate chunks of memory from the process heap by calling malloc subsystem subroutines. If the subroutine call succeeds, a process will be given the requested amount of virtual memory pages from the operating system, and those pages will be contiguously mapped in the process address space.

On AIX, the mapping addresses of newly allocated virtual pages are varied, depending on the user process model. For the detailed explanation about the available address range of the process heap, see 3.2, “The 32-bit user process model” on page 109 and 3.3, “The 64-bit user process model” on page 130.

The malloc subsystem performs the following fundamental memory operations:

AllocationAllocates the specified ...

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