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33 .Nd determine residency of memory pages
39 .Fn mincore "const void *addr" "size_t len" "char *vec"
43 system call determines whether each of the pages in the region beginning at
47 bytes is resident or mapped, depending on the value of sysctl
48 .Va vm.mincore_mapped .
49 .\"The beginning address,
51 .\"is first rounded down to a multiple of the page size (see
52 .\".Xr getpagesize 3 ) .
54 .\".Fa addr No + Fa len ,
55 .\"is rounded up to a multiple of the page size.
56 The status is returned in the
58 array, one character per page.
59 Each character is either 0 if the page is not resident, or a combination of
60 the following flags (defined in
62 .Bl -tag -width ".Dv MINCORE_REFERENCED_OTHER"
64 Page is in core (resident).
65 .It Dv MINCORE_REFERENCED
66 Page has been referenced by us.
67 .It Dv MINCORE_MODIFIED
68 Page has been modified by us.
69 .It Dv MINCORE_REFERENCED_OTHER
70 Page has been referenced.
71 .It Dv MINCORE_MODIFIED_OTHER
72 Page has been modified.
73 .It Dv MINCORE_PSIND(i)
74 Page is part of a large
76 page with size given by index
78 in the array returned by
84 If any bits in this mask are set, the page is part of a large
89 The information returned by
91 may be out of date by the time the system call returns.
92 The only way to ensure that a page is resident is to lock it into memory
99 sysctl is set to a non-zero value (default), only the current process'
100 mappings of the pages in the specified virtual address range are examined.
101 This does not preclude the system from returning
102 .Dv MINCORE_REFERENCED_OTHER
104 .Dv MINCORE_MODIFIED_OTHER
106 Otherwise, if the sysctl value is zero, all resident pages backing the
107 specified address range are examined, regardless of the mapping state.
108 .Sh IMPLEMENTATION NOTES
109 Prior to the introduction of
114 consisted of a single bit equal to
115 .Dv MINCORE_PSIND(1) .
116 In particular, applications compiled using the old value of
118 will not identify large pages with size index 2 as being large pages.
124 system call will fail if:
127 The virtual address range specified by the
131 arguments is not fully mapped.
135 argument points to an illegal address.
148 system call first appeared in