1mctl(3UCB) SunOS/BSD Compatibility Library Functions mctl(3UCB)
2
6 mctl - memory management control
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9 /usr/ucb/cc [ flag ... ] file ...
10 #include <sys/types.h>
11 #include <sys/mman.h>
12 int mctl(addr, len, function, arg)
14 caddr_t addr;
15 size_t len;
16 int function;
17 int arg;
18
21 mctl() applies a variety of control functions over pages identified by
22 the mappings established for the address range [addr, addr + len). The
23 function to be performed is identified by the argument function. Valid
24 functions are defined in <mman.h> as follows:
25 MC_LOCK Lock the pages in the range in memory. This function is
27 used to support mlock(). See mlock(3C) for semantics and
28 usage. arg is ignored.
29 MC_LOCKAS Lock the pages in the address space in memory. This
32 function is used to support mlockall(). See mlockall(3C)
33 for semantics and usage. addr and len are ignored. arg
34 is an integer built from the flags:
35 MCL_CURRENT Lock current mappings
37 MCL_FUTURE Lock future mappings
40 MC_SYNC Synchronize the pages in the range with their backing
44 storage. Optionally invalidate cache copies. This func‐
45 tion is used to support msync(). See msync(3C) for
46 semantics and usage. arg is used to represent the flags
47 argument to msync(). It is constructed from an OR of
48 the following values:
49 MS_SYNC Synchronized write
51 MS_ASYNC Return immediately
54 MS_INVALIDATE Invalidate mappings
57 MS_ASYNC returns after all I/O operations are scheduled.
59 MS_SYNC does not return until all I/O operations are
60 complete. Specify exactly one of MS_ASYNC or MS_SYNC.
61 MS_INVALIDATE invalidates all cached copies of data from
62 memory, requiring them to be re-obtained from the
63 object's permanent storage location upon the next refer‐
64 ence.
65 MC_UNLOCK Unlock the pages in the range. This function is used to
68 support munlock(). arg is ignored.
69 MC_UNLOCKAS Remove address space memory lock, and locks on all cur‐
72 rent mappings. This function is used to support
73 munlockall(). addr and len must have the value 0. arg is
74 ignored.
75
78 mctl() returns 0 on success, −1 on failure.
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81 mctl() fails if:
82 EAGAIN Some or all of the memory identified by the operation could
84 not be locked due to insufficient system resources.
85 EBUSY MS_INVALIDATE was specified and one or more of the pages is
88 locked in memory.
89 EINVAL addr is not a multiple of the page size as returned by getpa‐
92 gesize().
93 EINVAL addr and/or len do not have the value 0 when MC_LOCKAS or
96 MC_UNLOCKAS are specified.
97 EINVAL arg is not valid for the function specified.
100 EIO An I/O error occurred while reading from or writing to the
103 file system.
104 ENOMEM Addresses in the range [addr, addr + len) are invalid for the
107 address space of a process, or specify one or more pages
108 which are not mapped.
109 EPERM The process's effective user ID is not superuser and one of
112 MC_LOCK MC_LOCKAS, MC_UNLOCK, or MC_UNLOCKAS was specified.
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116 mmap(2), memcntl(2), getpagesize(3C), mlock(3C), mlockall(3C),
117 msync(3C)
118
120 Use of these interfaces should be restricted to only applications writ‐
121 ten on BSD platforms. Use of these interfaces with any of the system
122 libraries or in multi-thread applications is unsupported.
123SunOS 5.11 30 Oct 2007 mctl(3UCB)