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diff --git a/share/doc/gfortran/Extended-I_002fO-specifiers.html b/share/doc/gfortran/Extended-I_002fO-specifiers.html new file mode 100644 index 0000000..33463b8 --- /dev/null +++ b/share/doc/gfortran/Extended-I_002fO-specifiers.html @@ -0,0 +1,179 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1999-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). 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Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>The GNU Fortran Compiler: Extended I/O specifiers</title> + +<meta name="description" content="The GNU Fortran Compiler: Extended I/O specifiers"> +<meta name="keywords" content="The GNU Fortran Compiler: Extended I/O specifiers"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" rel="up" title="Extensions implemented in GNU Fortran"> +<link href="Legacy-PARAMETER-statements.html#Legacy-PARAMETER-statements" rel="next" title="Legacy PARAMETER statements"> +<link href="Bitwise-logical-operators.html#Bitwise-logical-operators" rel="previous" title="Bitwise logical operators"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Extended-I_002fO-specifiers"></a> +<div class="header"> +<p> +Next: <a href="Legacy-PARAMETER-statements.html#Legacy-PARAMETER-statements" accesskey="n" rel="next">Legacy PARAMETER statements</a>, Previous: <a href="Bitwise-logical-operators.html#Bitwise-logical-operators" accesskey="p" rel="previous">Bitwise logical operators</a>, Up: <a href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions implemented in GNU Fortran</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Extended-I_002fO-specifiers-1"></a> +<h4 class="subsection">5.1.32 Extended I/O specifiers</h4> +<a name="index-CARRIAGECONTROL"></a> +<a name="index-READONLY"></a> +<a name="index-SHARE"></a> +<a name="index-SHARED"></a> +<a name="index-NOSHARED"></a> +<a name="index-I_002fO-specifiers"></a> + +<p>GNU Fortran supports the additional legacy I/O specifiers +<code>CARRIAGECONTROL</code>, <code>READONLY</code>, and <code>SHARE</code> with the +compile flag <samp>-fdec</samp>, for compatibility. +</p> +<dl compact="compact"> +<dt><code>CARRIAGECONTROL</code></dt> +<dd><p>The <code>CARRIAGECONTROL</code> specifier allows a user to control line +termination settings between output records for an I/O unit. The specifier has +no meaning for readonly files. When <code>CARRAIGECONTROL</code> is specified upon +opening a unit for formatted writing, the exact <code>CARRIAGECONTROL</code> setting +determines what characters to write between output records. The syntax is: +</p> +<div class="smallexample"> +<pre class="smallexample">OPEN(..., CARRIAGECONTROL=cc) +</pre></div> + +<p>Where <em>cc</em> is a character expression that evaluates to one of the +following values: +</p> +<table> +<tr><td width="20%"><code>'LIST'</code></td><td width="80%">One line feed between records (default)</td></tr> +<tr><td width="20%"><code>'FORTRAN'</code></td><td width="80%">Legacy interpretation of the first character (see below)</td></tr> +<tr><td width="20%"><code>'NONE'</code></td><td width="80%">No separator between records</td></tr> +</table> + +<p>With <code>CARRIAGECONTROL='FORTRAN'</code>, when a record is written, the first +character of the input record is not written, and instead determines the output +record separator as follows: +</p> +<table> +<thead><tr><th width="30%">Leading character</th><th width="30%">Meaning</th><th width="40%">Output separating character(s)</th></tr></thead> +<tr><td width="30%"><code>'+'</code></td><td width="30%">Overprinting</td><td width="40%">Carriage return only</td></tr> +<tr><td width="30%"><code>'-'</code></td><td width="30%">New line</td><td width="40%">Line feed and carriage return</td></tr> +<tr><td width="30%"><code>'0'</code></td><td width="30%">Skip line</td><td width="40%">Two line feeds and carriage return</td></tr> +<tr><td width="30%"><code>'1'</code></td><td width="30%">New page</td><td width="40%">Form feed and carriage return</td></tr> +<tr><td width="30%"><code>'$'</code></td><td width="30%">Prompting</td><td width="40%">Line feed (no carriage return)</td></tr> +<tr><td width="30%"><code>CHAR(0)</code></td><td width="30%">Overprinting (no advance)</td><td width="40%">None</td></tr> +</table> + +</dd> +<dt><code>READONLY</code></dt> +<dd><p>The <code>READONLY</code> specifier may be given upon opening a unit, and is +equivalent to specifying <code>ACTION='READ'</code>, except that the file may not be +deleted on close (i.e. <code>CLOSE</code> with <code>STATUS="DELETE"</code>). The syntax +is: +</p> +<div class="smallexample"> +<pre class="smallexample"><code>OPEN(..., READONLY)</code> +</pre></div> + +</dd> +<dt><code>SHARE</code></dt> +<dd><p>The <code>SHARE</code> specifier allows system-level locking on a unit upon opening +it for controlled access from multiple processes/threads. The <code>SHARE</code> +specifier has several forms: +</p> +<div class="smallexample"> +<pre class="smallexample">OPEN(..., SHARE=sh) +OPEN(..., SHARED) +OPEN(..., NOSHARED) +</pre></div> + +<p>Where <em>sh</em> in the first form is a character expression that evaluates to +a value as seen in the table below. The latter two forms are aliases +for particular values of <em>sh</em>: +</p> +<table> +<thead><tr><th width="30%">Explicit form</th><th width="30%">Short form</th><th width="40%">Meaning</th></tr></thead> +<tr><td width="30%"><code>SHARE='DENYRW'</code></td><td width="30%"><code>NOSHARED</code></td><td width="40%">Exclusive (write) lock</td></tr> +<tr><td width="30%"><code>SHARE='DENYNONE'</code></td><td width="30%"><code>SHARED</code></td><td width="40%">Shared (read) lock</td></tr> +</table> + +<p>In general only one process may hold an exclusive (write) lock for a given file +at a time, whereas many processes may hold shared (read) locks for the same +file. +</p> +<p>The behavior of locking may vary with your operating system. On POSIX systems, +locking is implemented with <code>fcntl</code>. Consult your corresponding operating +system’s manual pages for further details. Locking via <code>SHARE=</code> is not +supported on other systems. +</p> +</dd> +</dl> + +<hr> +<div class="header"> +<p> +Next: <a href="Legacy-PARAMETER-statements.html#Legacy-PARAMETER-statements" accesskey="n" rel="next">Legacy PARAMETER statements</a>, Previous: <a href="Bitwise-logical-operators.html#Bitwise-logical-operators" accesskey="p" rel="previous">Bitwise logical operators</a>, Up: <a href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions implemented in GNU Fortran</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |