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+ <title>execline: the umask command</title>
+ <meta name="Description" content="execline: the umask command" />
+ <meta name="Keywords" content="execline command umask mask" />
+ <!-- <link rel="stylesheet" type="text/css" href="//skarnet.org/default.css" /> -->
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+
+<p>
+<a href="index.html">execline</a><br />
+<a href="//skarnet.org/software/">Software</a><br />
+<a href="//skarnet.org/">skarnet.org</a>
+</p>
+
+<h1> The <tt>umask</tt> program </h1>
+
+<p>
+<tt>umask</tt> changes its file mode creation mask, then executes a program.
+Alternatively, it can print the current mask.
+</p>
+
+<h2> Interface </h2>
+
+<pre>
+     umask [ -S ] [ <em>mask</em> ] [ <em>prog...</em> ]
+</pre>
+
+<p>
+When called with no argument, <tt>umask</tt> prints the value of the
+file mode creation mask of the invoking process, then exits 0.
+</p>
+
+<p>
+ When called with a <em>mask</em> argument, <tt>umask</tt> changes
+its file mode creation mask; then, if <em>prog...</em> is not empty, it execs
+into it.
+</p>
+
+<p>
+ <tt>umask</tt> interprets <em>mask</em> as specified by the
+<a href="https://pubs.opengroup.org/onlinepubs/9799919799/utilities/umask.html">POSIX
+specification for a <tt>umask</tt> external utility</a>.
+</p>
+
+<h2> Notes </h2>
+
+<ul>
+ <li> <tt>umask</tt> fully conforms to the
+<a href="https://pubs.opengroup.org/onlinepubs/9799919799/utilities/umask.html">POSIX
+specification</a>. When <em>prog...</em> is not empty, the behaviour of a
+<tt>umask</tt> utility is not specified by POSIX, so <tt>umask</tt> extends
+the spec to be actually useful and usable in an execline program. </li>
+</ul>
+
+</body>
+</html>