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munmap(2)							     munmap(2)

Name
       munmap -	unmaps memory of a character device

Syntax
       #include	<sys/types.h>
       #include	<sys/mman.h>

       caddr_t munmap(addr, len)
       caddr_t addr;
       size_t len;

Arguments
       addr	 Specifies  the	 address space of the calling process at which
		 the unmapping begins.

       len	 Specifies the number of bytes to unmap.

Description
       The system call unmaps a	specified number of bytes (len)	starting at  a
       specified address (addr)	from the address space of the calling process.
       You mapped this device in a previous call to Subsequent access  to  the
       unmapped	region results in a signal.  You cannot	unmap data, stack, and
       text segments using

       The system call rounds len to the nearest  multiple  of	page  size  as
       returned	by

       The  range  [addr,  addr	+ len] may contain more	than one mapped	region
       created by In this case,	unmaps all of the mapped regions.

Restrictions
       All of the mapped regions must be wholly	contained in the range	[addr,
       addr + len].  That is, addr must	be the beginning of some mapped	region
       and addr	+ len must be the end  of  some	 (possibly  different)	mapped
       region.

Return Value
       If  successful, returns 0.  Otherwise, it returns -1 and	sets the errno
       argument	to one of the errors listed in the Diagnostics section.

Diagnostics
       The call	to fails if one	or more	of the following is true:

       [EINVAL]	 The address you specified in addr is not a  multiple  of  the
		 page size as returned by

       [EINVAL]	 The  addresses	 in the	range [addr, addr + len] are not valid
		 in the	process	address	space.

       [EINVAL]	 All of	the segments being unmapped are	not entirely contained
		 in the	range [addr, addr + len].

See Also
       getpagesize(2), getsysinfo(2), mmap(2)

								     munmap(2)

Name | Syntax | Arguments | Description | Restrictions | Return Value | Diagnostics | See Also

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