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is a pointer to a variable that holds an error code:
OS_ERR_NONE
if If a memory block is available and returned to the application.
OS_ERR_MEM_INVALID_P_MEM
if If OS_CFG_ARG_CHK_EN is set to 1 in os_cfg.h: if p_mem is a NULL pointer.
OS_ERR_MEM_NO_FREE_BLKS
if If the memory partition does not contain additional memory blocks to allocate.
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