lib/boot-time.h

   1 /* Determine the time when the machine last booted.
   2    Copyright (C) 2023-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published
   6    by the Free Software Foundation, either version 3 of the License,
   7    or (at your option) any later version.
   8
   9    This file is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Bruno Haible <bruno@clisp.org>.  */
  18
  19 #ifndef _BOOT_TIME_H
  20 #define _BOOT_TIME_H
  21
  22 #include <time.h>
  23
  24 #ifdef __cplusplus
  25 extern "C" {
  26 #endif
  27
  28
  29 /* Store the approximate time when the machine last booted in *P_BOOT_TIME,
  30    and return 0.  If it cannot be determined, return -1.
  31
  32    This function is not multithread-safe, since on many platforms it
  33    invokes the functions setutxent, getutxent, endutxent.  These
  34    functions are needed because they may lock FILE (so that we don't
  35    read garbage when a concurrent process writes to FILE), but their
  36    drawback is that they have a common global state.  */
  37 extern int get_boot_time (struct timespec *p_boot_time);
  38
  39
  40 #ifdef __cplusplus
  41 }
  42 #endif
  43
  44 #endif /* _BOOT_TIME_H */