156 lines
2.5 KiB
HTML
156 lines
2.5 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>Summary</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Bash Guide for Beginners"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="More on variables"
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HREF="chap_10.html"><LINK
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REL="PREVIOUS"
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TITLE="Operations on variables"
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HREF="sect_10_03.html"><LINK
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REL="NEXT"
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TITLE="Exercises"
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HREF="sect_10_05.html"></HEAD
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><BODY
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CLASS="sect1"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Bash Guide for Beginners</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="sect_10_03.html"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 10. More on variables</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="sect_10_05.html"
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>Next</A
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="sect1"
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><H1
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CLASS="sect1"
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><A
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NAME="sect_10_04"
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></A
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>10.4. Summary</H1
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><P
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>Normally, a variable can hold any type of data, unless variables are declared explicitly. Constant variables are set using the <B
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CLASS="command"
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>readonly</B
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> built-in command.</P
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><P
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>An array holds a set of variables. If a type of data is declared, then all elements in the array will be set to hold only this type of data.</P
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><P
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>Bash features allow for substitution and transformation of variables <SPAN
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CLASS="QUOTE"
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>"on the fly"</SPAN
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>. Standard operations include calculating the length of a variable, arithmetic on variables, substituting variable content and substituting part of the content.</P
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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ALIGN="LEFT"
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SUMMARY="Footer navigation table"
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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><A
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HREF="sect_10_03.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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WIDTH="34%"
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>Home</A
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VALIGN="top"
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><A
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HREF="sect_10_05.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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><TR
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><TD
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
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>Operations on variables</TD
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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HREF="chap_10.html"
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>Up</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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>Exercises</TD
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></TR
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></TABLE
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></DIV
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></BODY
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></HTML
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> |