📄 sigprocmask.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"><html><head><!-- Copyright 1997 The Open Group, All Rights Reserved --><title>sigprocmask</title></head><body bgcolor=white><center><font size=2>The Single UNIX ® Specification, Version 2<br>Copyright © 1997 The Open Group</font></center><hr size=2 noshade><h4><a name = "tag_000_008_693"> </a>NAME</h4><blockquote>sigprocmask, pthread_sigmask - examine and change blocked signals</blockquote><h4><a name = "tag_000_008_694"> </a>SYNOPSIS</h4><blockquote><pre><code>#include <<a href="signal.h.html">signal.h</a>>int sigprocmask(int <i>how</i>, const sigset_t *<i>set</i>, sigset_t *<i>oset</i>);int pthread_sigmask(int <i>how</i>, const sigset_t *<i>set</i>, sigset_t *<i>oset</i>);</code></pre></blockquote><h4><a name = "tag_000_008_695"> </a>DESCRIPTION</h4><blockquote>In a single-threaded process, the<i>sigprocmask()</i>function allows the calling process to examine or change (or both)the signal mask of the calling thread.<p>If the argument<i>set</i>is not a null pointer, it points to a set of signals to be usedto change the currently blocked set.<p>The argument<i>how</i>indicates the way in which the set is changed, and consists ofone of the following values:<dl compact><dt>SIG_BLOCK<dd>The resulting set will be the union of the current set and the signalset pointed to by <i>set</i>.<dt>SIG_SETMASK<dd>The resulting set will be the signal set pointed to by <i>set</i>.<dt>SIG_UNBLOCK<dd>The resulting set will be the intersection of the currentset and the complement of the signal set pointed to by <i>set</i>.</dl><p>If the argument<i>oset</i>is not a null pointer, the previous mask is stored in the locationpointed to by <i>oset</i>.If <i>set</i> is a null pointer, the value of theargument <i>how</i> is not significant and the process' signalmask is unchanged; thus the call can be used to enquire aboutcurrently blocked signals.<p>If there are any pending unblocked signals after the call to<i>sigprocmask()</i>,at least one of those signals will be delivered before the call to<i>sigprocmask()</i>returns.<p>It is not possible to block those signals which cannot beignored.This is enforced by the system without causing an error to be indicated.<p>If any of the SIGFPE, SIGILL, SIGSEGV or SIGBUSsignals are generatedwhile they are blocked, the result is undefined, unless thesignal was generated by a function capable of sending a signal to a specific process or thread.<p>If<i>sigprocmask()</i>fails, the thread's signal mask is not changed.<p>The use of the<i>sigprocmask()</i>function is unspecified in a multi-threaded process.<p>The<i><a href="pthread_sigmask.html">pthread_sigmask()</a></i>function is used to examine or change (or both)the calling thread's signal mask,regardless of the number of threads in the process.The effect is the same as described for<i>sigprocmask()</i>,without the restriction that the call be made in a single-threadedprocess.</blockquote><h4><a name = "tag_000_008_696"> </a>RETURN VALUE</h4><blockquote>Upon successful completion,<i>sigprocmask()</i>returns 0. Otherwise -1 is returned,<i>errno</i>is set to indicate the error and the process' signal mask will be unchanged.<p>Upon successful completion<i><a href="pthread_sigmask.html">pthread_sigmask()</a></i>returns 0; otherwise it returns the corresponding error number.</blockquote><h4><a name = "tag_000_008_697"> </a>ERRORS</h4><blockquote>The<i>sigprocmask()</i>and<i><a href="pthread_sigmask.html">pthread_sigmask()</a></i>functions will fail if:<dl compact><dt>[EINVAL]<dd>The value of the <i>how</i> argument is not equal to one of thedefined values.</dl><p>The<i><a href="pthread_sigmask.html">pthread_sigmask()</a></i>function will not return an error code of [EINTR].</blockquote><h4><a name = "tag_000_008_698"> </a>EXAMPLES</h4><blockquote>None.</blockquote><h4><a name = "tag_000_008_699"> </a>APPLICATION USAGE</h4><blockquote>None.</blockquote><h4><a name = "tag_000_008_700"> </a>FUTURE DIRECTIONS</h4><blockquote>None.</blockquote><h4><a name = "tag_000_008_701"> </a>SEE ALSO</h4><blockquote><i><a href="sigaction.html">sigaction()</a></i>,<i><a href="sigaddset.html">sigaddset()</a></i>,<i><a href="sigdelset.html">sigdelset()</a></i>,<i><a href="sigemptyset.html">sigemptyset()</a></i>,<i><a href="sigfillset.html">sigfillset()</a></i>,<i><a href="sigismember.html">sigismember()</a></i>,<i><a href="sigpending.html">sigpending()</a></i>,<i><a href="sigqueue.html">sigqueue()</a></i>,<i><a href="sigsuspend.html">sigsuspend()</a></i>,<i><a href="signal.h.html"><signal.h></a></i>.</blockquote><h4>DERIVATION</h4><blockquote>Derived from the POSIX.1-1988 standard.</blockquote><hr size=2 noshade><center><font size=2>UNIX ® is a registered Trademark of The Open Group.<br>Copyright © 1997 The Open Group<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]</font></center><hr size=2 noshade></body></html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -