📄 tcgetpgrp.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"><html><head><!-- Copyright 1997 The Open Group, All Rights Reserved --><title>tcgetpgrp</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_009_471"> </a>NAME</h4><blockquote>tcgetpgrp - get the foreground process group ID</blockquote><h4><a name = "tag_000_009_472"> </a>SYNOPSIS</h4><blockquote><pre><code>#include <<a href="systypes.h.html">sys/types.h</a>>#include <<a href="unistd.h.html">unistd.h</a>>pid_t tcgetpgrp(int <i>fildes</i>);</code></pre></blockquote><h4><a name = "tag_000_009_473"> </a>DESCRIPTION</h4><blockquote>The<i>tcgetpgrp()</i>function will return the value of the process group ID of theforeground process group associated with the terminal.<p>If there is no foreground process group,<i>tcgetpgrp()</i>returns a value greater than 1 that does not match the process group ID of anyexisting process group.<p>The<i>tcgetpgrp()</i>function is allowed from a process that is a member of abackground process group; however, theinformation may be subsequently changed by a process that is amember of a foreground process group.</blockquote><h4><a name = "tag_000_009_474"> </a>RETURN VALUE</h4><blockquote>Upon successful completion,<i>tcgetpgrp()</i>returns the value of the process group ID of the foreground processassociated with the terminal. Otherwise, -1 is returned and<i>errno</i>is set to indicate the error.</blockquote><h4><a name = "tag_000_009_475"> </a>ERRORS</h4><blockquote>The<i>tcgetpgrp()</i>function will fail if:<dl compact><dt>[EBADF]<dd>The<i>fildes</i>argument is not a valid file descriptor.<dt>[ENOTTY]<dd>The calling process does not have a controlling terminal,or the file is not the controlling terminal.</dl></blockquote><h4><a name = "tag_000_009_476"> </a>EXAMPLES</h4><blockquote>None.</blockquote><h4><a name = "tag_000_009_477"> </a>APPLICATION USAGE</h4><blockquote>None.</blockquote><h4><a name = "tag_000_009_478"> </a>FUTURE DIRECTIONS</h4><blockquote>None.</blockquote><h4><a name = "tag_000_009_479"> </a>SEE ALSO</h4><blockquote><i><a href="setsid.html">setsid()</a></i>,<i><a href="setpgid.html">setpgid()</a></i>,<i><a href="tcsetpgrp.html">tcsetpgrp()</a></i>,<i><a href="systypes.h.html"><sys/types.h></a></i>,<i><a href="unistd.h.html"><unistd.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 + -