69 lines
2.5 KiB
C
Executable File
69 lines
2.5 KiB
C
Executable File
/* Report a SIGPIPE signal and exit.
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Copyright (C) 2008-2024 Free Software Foundation, Inc.
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>. */
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/* Written by Bruno Haible <bruno@clisp.org>, 2008. */
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/* SIGPIPE is the signal sent to a process calling write() on a pipe with no
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readers. Together with the signal, the write() call is terminated with
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return value -1, errno = EPIPE. Note that SIGPIPE is a *synchronous*
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signal: it occurs only during write(), without delay (unless blocked).
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The default reaction on SIGPIPE, namely terminating the process without
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an error message, is suitable for programs which only produce output to
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standard output and don't have side effects.
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When a program has side effects, other than writing to standard output, the
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suitable behaviour is either
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(a) to exit with an error message
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or - in certain cases, for example when writing to subprocesses -
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(b) to continue the operation without writing to the pipe/socket with
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no readers.
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This file provides support for (a).
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For (b), the program needs to know which of the output file descriptors
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has no readers. This is usually implemented by blocking the SIGPIPE signal
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and handling an EPIPE error indicator in all affected library calls
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(write(), send(), fwrite(), fflush(), fclose(), etc.). */
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#ifndef _SIGPIPE_DIE_H
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#define _SIGPIPE_DIE_H
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/* This file uses _Noreturn. */
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#if !_GL_CONFIG_H_INCLUDED
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#error "Please include config.h first."
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#endif
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* Emit an error message indicating a SIGPIPE signal, and terminate the
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process with an error code. */
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/*extern*/ _Noreturn void sigpipe_die (void);
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/* Install a SIGPIPE handler that invokes PREPARE_DIE and then emits an
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error message and exits. PREPARE_DIE may be NULL, meaning a no-op. */
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extern void install_sigpipe_die_handler (void (*prepare_die) (void));
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#ifdef __cplusplus
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}
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#endif
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#endif /* _SIGPIPE_DIE_H */
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