Storage Classes

<BODY LANG="EN"> <HR><center> <table border=1> <td><img height=36 width=36 alt="" src="http://www.cs.utah.edu/icons/latex2html/previous_fade.gif"></td> <td><A NAME="tex2html29" HREF="../../../classes/C/contents.shtml"><img height=36 width=36 alt="UP" src="http://www.cs.utah.edu/icons/latex2html/up.gif"></A></td> <td><A NAME="tex2html31" HREF="node1.shtml"><img height=36 width=36 alt="NEXT" src="http://www.cs.utah.edu/icons/latex2html/next.gif"></A></td> <td><a href="contents-c26.shtml"><img height=36 width=36 alt="CONTENTS" src="http://www.cs.utah.edu/icons/latex2html/toc.gif"></a></td> <td><a href="reset.hamlet"><img height=36 width=36 alt="RESET" src="http://www.cs.utah.edu/icons/latex2html/stop.gif"></a></td> <td><a href="copyright.html"><img height=36 width=36 alt="COPYRIGHT" src="http://www.cs.utah.edu/icons/latex2html/copyright.gif"></a></td> <td><a href="mailto:hamlet@cs.utah.edu"><img height=36 width=36 alt="FEEDBACK" src="http://www.cs.utah.edu/icons/latex2html/feedback.gif"></a></td> <td>     <a href="http://www.cs.utah.edu/%7Ehamlet/icons.html"><img height=36 width=36 alt=ABOUT src=http://www.cs.utah.edu/icons/latex2html/about.gif></a>  </td> </table> </center> <HR> <P> <H1>Storage Classes</H1> <P> Before beginning this lesson, you should read sections 7.1-7.2 and 7.4-7.7 of the text. We will be skipping over the remainder of the sections, but feel free to read them if you wish. <P> You should use level 5 of C-thru for this lesson. <P> We will be looking at a variety of topics in this lesson, but they all have to do with the visibility of variable names in programs with multiple functions and/or multiple files. We will focus on three kinds of <I>storage classes</I>: auto, extern, and static. <P> Every variable that you declare and use in a program belongs to a storage class. The storage class of a variable controls: <P> <UL> <LI> when (during program execution) it is allocated in memory, <LI> when (during program execution) it is initialized, <LI> where (in the program) it is visible, and <LI> when (during program execution) it is deallocated from memory. <P> </UL> <P> If you click below, I'll copy some more example files to your directory. <P> <A NAME="tex2html3" HREF="copytar0.hamlet"><img height=24 width=24 alt="EXECUTE" src="http://www.cs.utah.edu/icons/latex2html/execute.gif"></A>Click here to copy files <P> <HR><center> <table border=1> <td><img height=36 width=36 alt="" src="http://www.cs.utah.edu/icons/latex2html/previous_fade.gif"></td> <td><A NAME="tex2html29" HREF="../../../classes/C/contents.shtml"><img height=36 width=36 alt="UP" src="http://www.cs.utah.edu/icons/latex2html/up.gif"></A></td> <td><A NAME="tex2html31" HREF="node1.shtml"><img height=36 width=36 alt="NEXT" src="http://www.cs.utah.edu/icons/latex2html/next.gif"></A></td> <td><a href="contents-c26.shtml"><img height=36 width=36 alt="CONTENTS" src="http://www.cs.utah.edu/icons/latex2html/toc.gif"></a></td> <td><a href="reset.hamlet"><img height=36 width=36 alt="RESET" src="http://www.cs.utah.edu/icons/latex2html/stop.gif"></a></td> <td><a href="copyright.html"><img height=36 width=36 alt="COPYRIGHT" src="http://www.cs.utah.edu/icons/latex2html/copyright.gif"></a></td> <td><a href="mailto:hamlet@cs.utah.edu"><img height=36 width=36 alt="FEEDBACK" src="http://www.cs.utah.edu/icons/latex2html/feedback.gif"></a></td> <td>     <a href="http://www.cs.utah.edu/%7Ehamlet/icons.html"><img height=36 width=36 alt=ABOUT src=http://www.cs.utah.edu/icons/latex2html/about.gif></a>  </td> </table> </center> <HR><P><ADDRESS> <I><A NAME="tex2html1" HREF="http://www.cs.utah.edu/~hamlet">Hamlet Project</A> <BR> <A NAME="tex2html2" HREF="mailto:hamlet@cs.utah.edu">hamlet@cs.utah.edu</A></I> </ADDRESS> </BODY>