| /* Test for nonblocking read and write. |
| |
| Copyright (C) 2011-2020 Free Software Foundation, Inc. |
| |
| This program is free software: you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program 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 General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <https://www.gnu.org/licenses/>. */ |
| |
| /* A data block ought to be larger than the size of the in-kernel buffer. |
| Working values of PIPE_DATA_BLOCK_SIZE, depending on kernel: |
| |
| Platform PIPE_DATA_BLOCK_SIZE |
| |
| Linux >= 63489 |
| Linux/SPARC >= 126977 |
| Linux/IA-64, Linux/MIPS >= 253953 |
| Linux/PPC64 >= 1048576 |
| FreeBSD, OpenBSD, Mac OS X >= 65537 |
| AIX >= 32769 |
| HP-UX >= 8193 |
| IRIX >= 10241 |
| OSF/1 >= 262145 |
| Solaris <= 7 >= 10241 |
| Solaris >= 8 >= 20481 |
| z/OS >= 131073 |
| Cygwin >= 65537 |
| native Windows >= 4097 (depends on the _pipe argument) |
| */ |
| #if defined __MVS__ || defined __osf__ || (defined __linux__ && (defined __ia64__ || defined __mips__)) |
| # define PIPE_DATA_BLOCK_SIZE 270000 |
| #elif defined __linux__ && defined __sparc__ |
| # define PIPE_DATA_BLOCK_SIZE 140000 |
| #elif defined __linux__ && defined __powerpc__ |
| # define PIPE_DATA_BLOCK_SIZE 1100000 |
| #elif defined _WIN32 && !defined __CYGWIN__ |
| # define PIPE_DATA_BLOCK_SIZE 10000 |
| #else |
| # define PIPE_DATA_BLOCK_SIZE 70000 |
| #endif |
