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><I
>$replacement</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>${string//substring/replacement}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Replace <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>all</I
></SPAN
> matches of
	      <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
> with
	      <TT
CLASS="PARAMETER"
><I
>$replacement</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>${string/#substring/replacement}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>If <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>
	      matches <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>front</I
></SPAN
> end of
	      <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
>, substitute
	      <TT
CLASS="PARAMETER"
><I
>$replacement</I
></TT
> for
	      <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>${string/%substring/replacement}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>If <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>
	      matches <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>back</I
></SPAN
> end of
	      <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
>, substitute
	      <TT
CLASS="PARAMETER"
><I
>$replacement</I
></TT
> for
	      <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr match "$string" '$substring'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Length of matching <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>*
	        at beginning of <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr "$string" : '$substring'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Length of matching <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>*
	        at beginning of <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr index "$string" $substring</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Numerical position in <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
>
		of first character in <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>
		that matches</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr substr $string $position
	        $length</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Extract <TT
CLASS="PARAMETER"
><I
>$length</I
></TT
> characters
	        from <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
> starting at
	        <TT
CLASS="PARAMETER"
><I
>$position</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr match "$string"
	        '\($substring\)'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Extract <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>* at
	        beginning of <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr "$string" :
	        '\($substring\)'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Extract <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>* at
	        beginning of <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr match "$string"
	        '.*\($substring\)'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Extract <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>* at
	        end of <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>expr "$string" :
	        '.*\($substring\)'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Extract <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
>* at
	        end of <TT
CLASS="PARAMETER"
><I
>$string</I
></TT
></TD
></TR
></TBODY
></TABLE
><HR></DIV
><P
><B
CLASS="COMMAND"
>*</B
> Where <TT
CLASS="PARAMETER"
><I
>$substring</I
></TT
> is a
        <A
HREF="regexp.html#REGEXREF"
>regular expression</A
>.</P
><P
><A
NAME="MISCTAB"
></A
></P
><DIV
CLASS="TABLE"
><HR><A
NAME="AEN20886"
></A
><P
><B
>Table B-6. Miscellaneous Constructs</B
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><THEAD
><TR
><TH
ALIGN="LEFT"
VALIGN="TOP"
>Expression</TH
><TH
ALIGN="LEFT"
VALIGN="TOP"
>Interpretation</TH
></TR
></THEAD
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="regexp.html#BRACKETSREF"
>Brackets</A
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>if [ CONDITION ]</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="special-chars.html#LEFTBRACKET"
>Test construct</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>if [[ CONDITION ]]</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="tests.html#DBLBRACKETS"
>Extended test construct</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>Array[1]=element1</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="arrays.html#ARRAYREF"
>Array</A
> initialization</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
> [a-z]</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Range of characters within a <A
HREF="regexp.html#REGEXREF"
>Regular Expression</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Curly Brackets</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>${variable}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="parameter-substitution.html#PARAMSUBREF"
>Parameter substitution</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>${!variable}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="ivr.html#IVRREF"
>Indirect variable reference</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>{ command1; command2; . . . commandN; }</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="special-chars.html#CODEBLOCKREF"
>Block of code</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>{string1,string2,string3,...}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="special-chars.html#BRACEEXPREF"
>Brace expansion</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>{a..z}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="bashver3.html#BRACEEXPREF3"
>Extended brace expansion</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>{}</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Text replacement, after <A
HREF="moreadv.html#CURLYBRACKETSREF"
>find</A
> and <A
HREF="moreadv.html#XARGSCURLYREF"
>xargs</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="special-chars.html#PARENSREF"
>Parentheses</A
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>( command1; command2 )</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Command group executed within a <A
HREF="subshells.html#SUBSHELLSREF"
>subshell</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>Array=(element1 element2 element3)</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Array initialization</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>result=$(COMMAND)</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Execute command in subshell and assign result to
	        variable</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>&#62;(COMMAND)</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="process-sub.html#PROCESSSUBREF"
>Process substitution</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>&#60;(COMMAND)</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Process substitution</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="dblparens.html"
>Double Parentheses</A
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>(( var = 78 ))</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Integer arithmetic</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>var=$(( 20 + 5 ))</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Integer arithmetic, with variable assignment</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>(( var++ ))</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><I
CLASS="FIRSTTERM"
>C-style</I
> <A
HREF="dblparens.html#PLUSPLUSREF"
> variable increment</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>(( var-- ))</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><I
CLASS="FIRSTTERM"
>C-style</I
> <A
HREF="dblparens.html#PLUSPLUSREF"
> variable decrement</A
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>(( var0 = var1&#60;98?9:21 ))</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><I
CLASS="FIRSTTERM"
>C-style</I
> <A
HREF="special-chars.html#CSTRINARY"
> trinary</A
> operation</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="quoting.html#QUOTINGREF"
>Quoting</A
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>"$variable"</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>"Weak" quoting</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>'string'</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>"Strong" quoting</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><A
HREF="commandsub.html#BACKQUOTESREF"
>Back Quotes</A
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>&nbsp;</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="OPTION"
>result=`COMMAND`</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Execute command in subshell and assign result
	      to variable</TD
></TR
></TBODY
></TABLE
><HR></DIV
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><HR
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HREF="contributed-scripts.html"
ACCESSKEY="P"
>Prev</A
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