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The C and C++ Include Header Files
cat -n /usr/include/x86_64-linux-gnu/bits/mman-shared.h
1 /* Memory-mapping-related declarations/definitions, not architecture-specific. 2 Copyright (C) 2017-2026 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #ifndef _SYS_MMAN_H 20 # error "Never use <bits/mman-shared.h> directly; include <sys/mman.h> instead." 21 #endif 22 23 #ifdef __USE_GNU 24 /* Flags for mremap. */ 25 # define MREMAP_MAYMOVE 1 26 # define MREMAP_FIXED 2 27 # define MREMAP_DONTUNMAP 4 28 29 /* Flags for memfd_create. */ 30 # ifndef MFD_CLOEXEC 31 # define MFD_CLOEXEC 1U 32 # define MFD_ALLOW_SEALING 2U 33 # define MFD_HUGETLB 4U 34 # endif 35 # ifndef MFD_NOEXEC_SEAL 36 # define MFD_NOEXEC_SEAL 8U 37 # define MFD_EXEC 0x10U 38 # endif 39 40 /* Flags for mlock2. */ 41 # ifndef MLOCK_ONFAULT 42 # define MLOCK_ONFAULT 1U 43 # endif 44 45 /* Access restrictions for pkey_alloc. */ 46 # define PKEY_UNRESTRICTED 0x0 47 # define PKEY_DISABLE_ACCESS 0x1 48 # define PKEY_DISABLE_WRITE 0x2 49 50 __BEGIN_DECLS 51 52 /* Create a new memory file descriptor. NAME is a name for debugging. 53 FLAGS is a combination of the MFD_* constants. */ 54 int memfd_create (const char *__name, unsigned int __flags) __THROW; 55 56 /* Lock pages from ADDR (inclusive) to ADDR + LENGTH (exclusive) into 57 memory. FLAGS is a combination of the MLOCK_* flags above. */ 58 int mlock2 (const void *__addr, size_t __length, unsigned int __flags) __THROW 59 __attr_access_none (1); 60 61 /* Allocate a new protection key, with the PKEY_DISABLE_* bits 62 specified in ACCESS_RESTRICTIONS. The protection key mask for the 63 current thread is updated to match the access privilege for the new 64 key. */ 65 int pkey_alloc (unsigned int __flags, unsigned int __access_restrictions) __THROW; 66 67 /* Update the access restrictions for the current thread for KEY, which must 68 have been allocated using pkey_alloc. */ 69 int pkey_set (int __key, unsigned int __access_restrictions) __THROW; 70 71 /* Return the access restrictions for the current thread for KEY, which must 72 have been allocated using pkey_alloc. */ 73 int pkey_get (int __key) __THROW; 74 75 /* Free an allocated protection key, which must have been allocated 76 using pkey_alloc. */ 77 int pkey_free (int __key) __THROW; 78 79 /* Apply memory protection flags for KEY to the specified address 80 range. */ 81 int pkey_mprotect (void *__addr, size_t __len, int __prot, int __pkey) __THROW; 82 83 /* Seal the address range to avoid further modifications, such as remapping to 84 shrink or expand the VMA, changing protection permission with mprotect, 85 unmap with munmap, or destructive semantics such as madvise with 86 MADV_DONTNEED. 87 88 The address range must be a valid VMA, without any gaps (unallocated 89 memory) between the start and end, and ADDR must be page-aligned (LEN will 90 be page-aligned implicitly). */ 91 int mseal (void *__addr, size_t __len, unsigned long flags) __THROW; 92 93 __END_DECLS 94 95 #endif /* __USE_GNU */
