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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-24 04:52:24 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-24 04:52:24 +0000 |
commit | 100d1b33f088fd38f69129afff7f9c2a1e084a57 (patch) | |
tree | 5bf6b0bb14f22ecf0a5e9439fdd4c4758402400c /man/man3/bsd_signal.3 | |
parent | Releasing progress-linux version 6.7-2~progress7.99u1. (diff) | |
download | manpages-100d1b33f088fd38f69129afff7f9c2a1e084a57.tar.xz manpages-100d1b33f088fd38f69129afff7f9c2a1e084a57.zip |
Merging upstream version 6.8.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'man/man3/bsd_signal.3')
-rw-r--r-- | man/man3/bsd_signal.3 | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/man/man3/bsd_signal.3 b/man/man3/bsd_signal.3 new file mode 100644 index 0000000..183ab2e --- /dev/null +++ b/man/man3/bsd_signal.3 @@ -0,0 +1,112 @@ +'\" t +.\" Copyright (c) 2007 Michael Kerrisk <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH bsd_signal 3 2024-05-02 "Linux man-pages (unreleased)" +.SH NAME +bsd_signal \- signal handling with BSD semantics +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <signal.h> +.P +.B typedef void (*sighandler_t)(int); +.P +.BI "sighandler_t bsd_signal(int " signum ", sighandler_t " handler ); +.fi +.P +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR bsd_signal (): +.nf + Since glibc 2.26: + _XOPEN_SOURCE >= 500 +.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED + && ! (_POSIX_C_SOURCE >= 200809L) + glibc 2.25 and earlier: + _XOPEN_SOURCE +.fi +.SH DESCRIPTION +The +.BR bsd_signal () +function takes the same arguments, and performs the same task, as +.BR signal (2). +.P +The difference between the two is that +.BR bsd_signal () +is guaranteed to provide reliable signal semantics, that is: +a) the disposition of the signal is not reset to the default +when the handler is invoked; +b) delivery of further instances of the signal is blocked while +the signal handler is executing; and +c) if the handler interrupts a blocking system call, +then the system call is automatically restarted. +A portable application cannot rely on +.BR signal (2) +to provide these guarantees. +.SH RETURN VALUE +The +.BR bsd_signal () +function returns the previous value of the signal handler, or +.B SIG_ERR +on error. +.SH ERRORS +As for +.BR signal (2). +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR bsd_signal () +T} Thread safety MT-Safe +.TE +.SH VERSIONS +Use of +.BR bsd_signal () +should be avoided; use +.BR sigaction (2) +instead. +.P +On modern Linux systems, +.BR bsd_signal () +and +.BR signal (2) +are equivalent. +But on older systems, +.BR signal (2) +provided unreliable signal semantics; see +.BR signal (2) +for details. +.P +The use of +.I sighandler_t +is a GNU extension; +this type is defined only if the +.B _GNU_SOURCE +feature test macro is defined. +.SH STANDARDS +None. +.SH HISTORY +4.2BSD, POSIX.1-2001. +Removed in POSIX.1-2008, +recommending the use of +.BR sigaction (2) +instead. +.SH SEE ALSO +.BR sigaction (2), +.BR signal (2), +.BR sysv_signal (3), +.BR signal (7) |