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diff --git a/upstream/archlinux/man3p/sigemptyset.3p b/upstream/archlinux/man3p/sigemptyset.3p new file mode 100644 index 00000000..f1aac401 --- /dev/null +++ b/upstream/archlinux/man3p/sigemptyset.3p @@ -0,0 +1,120 @@ +'\" et +.TH SIGEMPTYSET "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +sigemptyset +\(em initialize and empty a signal set +.SH SYNOPSIS +.LP +.nf +#include <signal.h> +.P +int sigemptyset(sigset_t *\fIset\fP); +.fi +.SH DESCRIPTION +The +\fIsigemptyset\fR() +function initializes the signal set pointed to by +.IR set , +such that all signals defined in POSIX.1\(hy2008 are excluded. +.SH "RETURN VALUE" +Upon successful completion, +\fIsigemptyset\fR() +shall return 0; otherwise, it shall return \-1 and set +.IR errno +to indicate the error. +.SH ERRORS +No errors are defined. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +The implementation of the +\fIsigemptyset\fR() +(or +\fIsigfillset\fR()) +function could quite trivially clear (or set) all the bits in the +signal set. Alternatively, it would be reasonable to initialize part +of the structure, such as a version field, to permit +binary-compatibility between releases where the size of the set +varies. For such reasons, either +\fIsigemptyset\fR() +or +\fIsigfillset\fR() +must be called prior to any other use of the signal set, even if such +use is read-only (for example, as an argument to +\fIsigpending\fR()). +This function is not intended for dynamic allocation. +.P +The +\fIsigfillset\fR() +and +\fIsigemptyset\fR() +functions require that the resulting signal set include (or exclude) +all the signals defined in this volume of POSIX.1\(hy2017. Although it is outside the scope of +\&this volume of POSIX.1\(hy2017 to place this requirement on signals that are implemented as +extensions, it is recommended that implementation-defined signals +also be affected by these functions. However, there may be a good +reason for a particular signal not to be affected. For example, +blocking or ignoring an implementation-defined signal may have +undesirable side-effects, whereas the default action for that signal is +harmless. In such a case, it would be preferable for such a signal to +be excluded from the signal set returned by +\fIsigfillset\fR(). +.P +In early proposals there was no distinction between invalid and +unsupported signals (the names of optional signals that were not +supported by an implementation were not defined by that +implementation). The +.BR [EINVAL] +error was thus specified as a required error for invalid signals. With +that distinction, it is not necessary to require implementations of +these functions to determine whether an optional signal is actually +supported, as that could have a significant performance impact for +little value. The error could have been required for invalid signals +and optional for unsupported signals, but this seemed unnecessarily +complex. Thus, the error is optional in both cases. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.ad l +.IR "Section 2.4" ", " "Signal Concepts", +.IR "\fIpthread_sigmask\fR\^(\|)", +.IR "\fIsigaction\fR\^(\|)", +.IR "\fIsigaddset\fR\^(\|)", +.IR "\fIsigdelset\fR\^(\|)", +.IR "\fIsigfillset\fR\^(\|)", +.IR "\fIsigismember\fR\^(\|)", +.IR "\fIsigpending\fR\^(\|)", +.IR "\fIsigsuspend\fR\^(\|)" +.ad b +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<signal.h>\fP" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +In the event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |