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diff --git a/man2/mincore.2 b/man2/mincore.2 new file mode 100644 index 0000000..9ffca56 --- /dev/null +++ b/man2/mincore.2 @@ -0,0 +1,158 @@ +.\" Copyright (C) 2001 Bert Hubert <ahu@ds9a.nl> +.\" and Copyright (C) 2007 Michael Kerrisk <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" Created Sun Jun 3 17:23:32 2001 by bert hubert <ahu@ds9a.nl> +.\" Slightly adapted, following comments by Hugh Dickins, aeb, 2001-06-04. +.\" Modified, 20 May 2003, Michael Kerrisk <mtk.manpages@gmail.com> +.\" Modified, 30 Apr 2004, Michael Kerrisk <mtk.manpages@gmail.com> +.\" 2005-04-05 mtk, Fixed error descriptions +.\" after message from <gordon.jin@intel.com> +.\" 2007-01-08 mtk, rewrote various parts +.\" +.TH mincore 2 2023-03-30 "Linux man-pages 6.05.01" +.SH NAME +mincore \- determine whether pages are resident in memory +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <sys/mman.h> +.PP +.BI "int mincore(void " addr [. length "], size_t " length ", unsigned char *" vec ); +.fi +.PP +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR mincore (): +.nf + Since glibc 2.19: + _DEFAULT_SOURCE + glibc 2.19 and earlier: + _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +.BR mincore () +returns a vector that indicates whether pages +of the calling process's virtual memory are resident in core (RAM), +and so will not cause a disk access (page fault) if referenced. +The kernel returns residency information about the pages +starting at the address +.IR addr , +and continuing for +.I length +bytes. +.PP +The +.I addr +argument must be a multiple of the system page size. +The +.I length +argument need not be a multiple of the page size, +but since residency information is returned for whole pages, +.I length +is effectively rounded up to the next multiple of the page size. +One may obtain the page size +.RB ( PAGE_SIZE ) +using +.IR sysconf(_SC_PAGESIZE) . +.PP +The +.I vec +argument must point to an array containing at least +.I "(length+PAGE_SIZE\-1) / PAGE_SIZE" +bytes. +On return, +the least significant bit of each byte will be set if +the corresponding page is currently resident in memory, +and be clear otherwise. +(The settings of the other bits in each byte are undefined; +these bits are reserved for possible later use.) +Of course the information returned in +.I vec +is only a snapshot: pages that are not +locked in memory can come and go at any moment, and the contents of +.I vec +may already be stale by the time this call returns. +.SH RETURN VALUE +On success, +.BR mincore () +returns zero. +On error, \-1 is returned, and +.I errno +is set to indicate the error. +.SH ERRORS +.B EAGAIN +kernel is temporarily out of resources. +.TP +.B EFAULT +.I vec +points to an invalid address. +.TP +.B EINVAL +.I addr +is not a multiple of the page size. +.TP +.B ENOMEM +.I length +is greater than +.RI ( TASK_SIZE " \- " addr ). +(This could occur if a negative value is specified for +.IR length , +since that value will be interpreted as a large +unsigned integer.) +In Linux 2.6.11 and earlier, the error +.B EINVAL +was returned for this condition. +.TP +.B ENOMEM +.I addr +to +.I addr ++ +.I length +contained unmapped memory. +.SH STANDARDS +None. +.SH HISTORY +Linux 2.3.99pre1, +glibc 2.2. +.PP +First appeared in 4.4BSD. +.PP +NetBSD, FreeBSD, OpenBSD, Solaris 8, +AIX 5.1, SunOS 4.1. +.SH BUGS +Before Linux 2.6.21, +.BR mincore () +did not return correct information for +.B MAP_PRIVATE +mappings, or for nonlinear mappings (established using +.BR remap_file_pages (2)). +.\" Linux (up to now, 2.6.5), +.\" .B mincore +.\" does not return correct information for MAP_PRIVATE mappings: +.\" for a MAP_PRIVATE file mapping, +.\" .B mincore +.\" returns the residency of the file pages, rather than any +.\" modified process-private pages that have been copied on write; +.\" for a MAP_PRIVATE mapping of +.\" .IR /dev/zero , +.\" .B mincore +.\" always reports pages as nonresident; +.\" and for a MAP_PRIVATE, MAP_ANONYMOUS mapping, +.\" .B mincore +.\" always fails with the error +.\" .BR ENOMEM . +.SH SEE ALSO +.BR fincore (1), +.BR madvise (2), +.BR mlock (2), +.BR mmap (2), +.BR posix_fadvise (2), +.BR posix_madvise (3) |