<html lang="en"> <head> <title>C_SIZEOF - The GNU Fortran Compiler</title> <meta http-equiv="Content-Type" content="text/html"> <meta name="description" content="The GNU Fortran Compiler"> <meta name="generator" content="makeinfo 4.13"> <link title="Top" rel="start" href="index.html#Top"> <link rel="up" href="Intrinsic-Procedures.html#Intrinsic-Procedures" title="Intrinsic Procedures"> <link rel="prev" href="C_005fLOC.html#C_005fLOC" title="C_LOC"> <link rel="next" href="CEILING.html#CEILING" title="CEILING"> <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> <!-- Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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). A copy of the license is included in the section entitled ``GNU Free Documentation License''. (a) The FSF's Front-Cover Text is: A GNU Manual (b) The FSF's Back-Cover Text is: You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development.--> <meta http-equiv="Content-Style-Type" content="text/css"> <style type="text/css"><!-- pre.display { font-family:inherit } pre.format { font-family:inherit } pre.smalldisplay { font-family:inherit; font-size:smaller } pre.smallformat { font-family:inherit; font-size:smaller } pre.smallexample { font-size:smaller } pre.smalllisp { font-size:smaller } span.sc { font-variant:small-caps } span.roman { font-family:serif; font-weight:normal; } span.sansserif { font-family:sans-serif; font-weight:normal; } --></style> </head> <body> <div class="node"> <a name="C_SIZEOF"></a> <a name="C_005fSIZEOF"></a> <p> Next: <a rel="next" accesskey="n" href="CEILING.html#CEILING">CEILING</a>, Previous: <a rel="previous" accesskey="p" href="C_005fLOC.html#C_005fLOC">C_LOC</a>, Up: <a rel="up" accesskey="u" href="Intrinsic-Procedures.html#Intrinsic-Procedures">Intrinsic Procedures</a> <hr> </div> <h3 class="section">8.41 <code>C_SIZEOF</code> — Size in bytes of an expression</h3> <p><a name="index-C_005fSIZEOF-479"></a><a name="index-expression-size-480"></a><a name="index-size-of-an-expression-481"></a> <dl> <dt><em>Description</em>:<dd><code>C_SIZEOF(X)</code> calculates the number of bytes of storage the expression <code>X</code> occupies. <br><dt><em>Standard</em>:<dd>Fortran 2008 <br><dt><em>Class</em>:<dd>Inquiry function of the module <code>ISO_C_BINDING</code> <br><dt><em>Syntax</em>:<dd><code>N = C_SIZEOF(X)</code> <br><dt><em>Arguments</em>:<dd> <p><table summary=""><tr align="left"><td valign="top" width="15%"><var>X</var> </td><td valign="top" width="70%">The argument shall be an interoperable data entity. <br></td></tr></table> <br><dt><em>Return value</em>:<dd>The return value is of type integer and of the system-dependent kind <code>C_SIZE_T</code> (from the <code>ISO_C_BINDING</code> module). Its value is the number of bytes occupied by the argument. If the argument has the <code>POINTER</code> attribute, the number of bytes of the storage area pointed to is returned. If the argument is of a derived type with <code>POINTER</code> or <code>ALLOCATABLE</code> components, the return value doesn't account for the sizes of the data pointed to by these components. <br><dt><em>Example</em>:<dd> <pre class="smallexample"> use iso_c_binding integer(c_int) :: i real(c_float) :: r, s(5) print *, (c_sizeof(s)/c_sizeof(r) == 5) end </pre> <p>The example will print <code>.TRUE.</code> unless you are using a platform where default <code>REAL</code> variables are unusually padded. <br><dt><em>See also</em>:<dd><a href="SIZEOF.html#SIZEOF">SIZEOF</a>, <a href="STORAGE_005fSIZE.html#STORAGE_005fSIZE">STORAGE_SIZE</a> </dl> </body></html>