munmap(2)                                                  munmap(2)


       NAME
             munmap - unmap pages of memory

       SYNOPSIS
             #include <sys/types.h>
             #include <sys/mman.h>
             int munmap(caddr_t addr, size_t len);

       DESCRIPTION
             The function munmap removes the mappings for pages in the
             range (addr, addr + len).  Further references to these pages
             will result in the delivery of a SIGSEGV signal to the
             process.

             The function mmap often performs an implicit munmap.

          Return Values
             On success, munmap returns 0.  On failure, munmap returns -1
             and sets errno to identify the error.

          Errors
             In the following conditions, munmap fails and sets errno to:

            EINVAL addr is not a multiple of the page size as returned by
                    sysconf.

            EINVAL Addresses in the range (addr, addr + len) are outside
                    the valid range for the address space of a process.

            EINVAL The argument len has a value less than or equal to 0.

       REFERENCES
             mmap(2), sysconf(3C)

       NOTICES
          Considerations for Threads Programming
             Sibling threads share (by definition) the same address space;
             modifications to the address space by one can be perceived by
             the others.









                           Copyright 1994 Novell, Inc.               Page 1