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<h4 class="subsection">7.1.3 Interoperable Global Variables</h4>
<p>Variables can be made accessible from C using the C binding attribute,
optionally together with specifying a binding name. Those variables
have to be declared in the declaration part of a <code>MODULE</code>,
be of interoperable type, and have neither the <code>pointer</code> nor
the <code>allocatable</code> attribute.
<pre class="smallexample"> MODULE m
USE myType_module
USE ISO_C_BINDING
integer(C_INT), bind(C, name="_MyProject_flags") :: global_flag
type(myType), bind(C) :: tp
END MODULE
</pre>
<p>Here, <code>_MyProject_flags</code> is the case-sensitive name of the variable
as seen from C programs while <code>global_flag</code> is the case-insensitive
name as seen from Fortran. If no binding name is specified, as for
<var>tp</var>, the C binding name is the (lowercase) Fortran binding name.
If a binding name is specified, only a single variable may be after the
double colon. Note of warning: You cannot use a global variable to
access <var>errno</var> of the C library as the C standard allows it to be
a macro. Use the <code>IERRNO</code> intrinsic (GNU extension) instead.
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