| /* Detect the number of processors. | |
| Copyright (C) 2009-2023 Free Software Foundation, Inc. | |
| This file is free software: you can redistribute it and/or modify | |
| it under the terms of the GNU Lesser General Public License as | |
| published by the Free Software Foundation; either version 2.1 of the | |
| License, or (at your option) any later version. | |
| This file is distributed in the hope that it will be useful, | |
| but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| GNU Lesser General Public License for more details. | |
| You should have received a copy of the GNU Lesser General Public License | |
| along with this program. If not, see <https://www.gnu.org/licenses/>. */ | |
| /* Written by Glen Lenker and Bruno Haible. */ | |
| /* Allow the use in C++ code. */ | |
| extern "C" { | |
| /* A "processor" in this context means a thread execution unit, that is either | |
| - an execution core in a (possibly multi-core) chip, in a (possibly multi- | |
| chip) module, in a single computer, or | |
| - a thread execution unit inside a core | |
| (hyper-threading, see <https://en.wikipedia.org/wiki/Hyper-threading>). | |
| Which of the two definitions is used, is unspecified. */ | |
| enum nproc_query | |
| { | |
| NPROC_ALL, /* total number of processors */ | |
| NPROC_CURRENT, /* processors available to the current process */ | |
| NPROC_CURRENT_OVERRIDABLE /* likewise, but overridable through the | |
| OMP_NUM_THREADS environment variable */ | |
| }; | |
| /* Return the total number of processors. The result is guaranteed to | |
| be at least 1. */ | |
| extern unsigned long int num_processors (enum nproc_query query); | |
| } | |