NAME

kmem_zalloc − allocate and clear space from kernel free memory

SYNOPSIS

#include <sys/types.h>
#include <sys/kmem.h>
void ∗kmem_zalloc(size_t size, int flags);

ARGUMENTS

size Number of bytes to allocate. 

flags Determines if caller may sleep to wait for free space.  Possible flags are KM_SLEEP to sleep while waiting for free space, and KM_NOSLEEP to return NULL if space is not available. 

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI). 

DESCRIPTION

This function allocates size bytes of storage from kernel free space, clears it, and returns a pointer to the allocated memory.  If flags has KM_SLEEP set, the caller may sleep until free space is available.  If flags has KM_NOSLEEP set and space is not available, NULL will be returned. 

RETURN VALUES

kmem_zalloc() returns NULL if memory cannot be allocated.  Otherwise, it returns a pointer to the allocated space. 

CONTEXT

kmem_zalloc() can be called from interrupt context only if the KM_NOSLEEP flag is set. It can be called from user context with any valid flags.

SEE ALSO

freerbuf(9F), getrbuf(9F), kmem_alloc(9F), kmem_free(9F)

Writing Device Drivers

WARNINGS

Memory allocated by kmem_zalloc() is not paged. Available memory is therefore limited.  Excessive use of this memory is likely to affect overall system performance.

SunOS 5.4  —  Last change: 11 Apr 1991