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The C and C++ Include Header Files

cat -n /usr/include/x86_64-linux-gnu/sys/pidfd.h

     1	/* Wrapper for file descriptors that refers to a process functions.
     2	   Copyright (C) 2022-2026 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 _PIDFD_H
    20	
    21	#include <fcntl.h>
    22	#include <bits/types/siginfo_t.h>
    23	#include <sys/ioctl.h>
    24	
    25	#define PIDFD_NONBLOCK O_NONBLOCK
    26	#define PIDFD_THREAD O_EXCL
    27	
    28	#define PIDFD_SIGNAL_THREAD (1UL << 0)
    29	#define PIDFD_SIGNAL_THREAD_GROUP (1UL << 1)
    30	#define PIDFD_SIGNAL_PROCESS_GROUP (1UL << 2)
    31	
    32	#define PIDFS_IOCTL_MAGIC 0xFF
    33	
    34	#define PIDFD_GET_CGROUP_NAMESPACE            _IO(PIDFS_IOCTL_MAGIC, 1)
    35	#define PIDFD_GET_IPC_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 2)
    36	#define PIDFD_GET_MNT_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 3)
    37	#define PIDFD_GET_NET_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 4)
    38	#define PIDFD_GET_PID_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 5)
    39	#define PIDFD_GET_PID_FOR_CHILDREN_NAMESPACE  _IO(PIDFS_IOCTL_MAGIC, 6)
    40	#define PIDFD_GET_TIME_NAMESPACE              _IO(PIDFS_IOCTL_MAGIC, 7)
    41	#define PIDFD_GET_TIME_FOR_CHILDREN_NAMESPACE _IO(PIDFS_IOCTL_MAGIC, 8)
    42	#define PIDFD_GET_USER_NAMESPACE              _IO(PIDFS_IOCTL_MAGIC, 9)
    43	#define PIDFD_GET_UTS_NAMESPACE               _IO(PIDFS_IOCTL_MAGIC, 10)
    44	
    45	/* Sentinels to avoid allocating a file descriptor to refer to own process.  */
    46	#define PIDFD_SELF_THREAD                     -10000
    47	#define PIDFD_SELF_THREAD_GROUP               -10001
    48	#define PIDFD_SELF                            PIDFD_SELF_THREAD
    49	#define PIDFD_SELF_PROCESS                    PIDFD_SELF_THREAD_GROUP
    50	
    51	
    52	/* Flags for pidfd_info.  */
    53	
    54	/* Always returned, even if not requested */
    55	#define PIDFD_INFO_PID                        (1UL << 0)
    56	/* Always returned, even if not requested */
    57	#define PIDFD_INFO_CREDS                      (1UL << 1)
    58	/* Always returned if available, even if not requested */
    59	#define PIDFD_INFO_CGROUPID                   (1UL << 2)
    60	/* Only returned if requested. */
    61	#define PIDFD_INFO_EXIT                       (1UL << 3)
    62	/* Only returned if requested. */
    63	#define PIDFD_INFO_COREDUMP                   (1UL << 4)
    64	
    65	
    66	/* Value for coredump_mask in pidfd_info.  Only valid if PIDFD_INFO_COREDUMP
    67	   is set in mask.  */
    68	
    69	/* Did crash and... */
    70	#define PIDFD_COREDUMPED                      (1U << 0)
    71	/* coredumping generation was skipped. */
    72	#define PIDFD_COREDUMP_SKIP                   (1U << 1)
    73	/* coredump was done as the user. */
    74	#define PIDFD_COREDUMP_USER                   (1U << 2)
    75	/* coredump was done as root. */
    76	#define PIDFD_COREDUMP_ROOT                   (1U << 3)
    77	
    78	struct pidfd_info
    79	{
    80	  __uint64_t mask;
    81	  __uint64_t cgroupid;
    82	  __uint32_t pid;
    83	  __uint32_t tgid;
    84	  __uint32_t ppid;
    85	  __uint32_t ruid;
    86	  __uint32_t rgid;
    87	  __uint32_t euid;
    88	  __uint32_t egid;
    89	  __uint32_t suid;
    90	  __uint32_t sgid;
    91	  __uint32_t fsuid;
    92	  __uint32_t fsgid;
    93	  __int32_t  exit_code;
    94	  __uint32_t coredump_mask;
    95	  __uint32_t __spare1;
    96	};
    97	
    98	/* sizeof first published struct */
    99	#define PIDFD_INFO_SIZE_VER0                  64
   100	
   101	#define PIDFD_GET_INFO                        _IOWR(PIDFS_IOCTL_MAGIC, 11, struct pidfd_info)
   102	
   103	/* Returns a file descriptor that refers to the process PID.  The
   104	   close-on-exec is set on the file descriptor.  */
   105	extern int pidfd_open (__pid_t __pid, unsigned int __flags) __THROW;
   106	
   107	/* Duplicates an existing file descriptor TARGETFD in the process referred
   108	   by the PIDFD file descriptor PIDFD.
   109	
   110	   The FLAGS argument is reserved for future use, it must be specified
   111	   as 0.  */
   112	extern int pidfd_getfd (int __pidfd, int __targetfd,
   113				unsigned int __flags) __THROW;
   114	
   115	/* Sends the signal SIG to the target process referred by the PIDFD.  If
   116	   INFO points to a siginfo_t buffer, it will be populated.  */
   117	extern int pidfd_send_signal (int __pidfd, int __sig, siginfo_t *__info,
   118				      unsigned int __flags) __THROW;
   119	
   120	/* Query the process ID (PID) from process descriptor FD.  Return the PID
   121	   or -1 in case of an error.  */
   122	extern pid_t pidfd_getpid (int __fd) __THROW;
   123	
   124	#endif /* _PIDFD_H  */