xrefindex.html

Shall高级编程

         in a table
	   <UL
><LI
><P
><A
HREF="contributed-scripts.html#HASHEX2_0"
><I
CLASS="FIRSTTERM"
>Example
	   script</I
></A
></P
></LI
></UL
></P
><P
><A
HREF="textproc.html#HEADREF"
>head</A
>, <I
CLASS="FIRSTTERM"
>echo</I
>
        to <TT
CLASS="FILENAME"
>stdout</TT
> lines at the beginning of a text
        file</P
><P
><A
HREF="internal.html#HELPREF"
>help</A
>, gives usage summary of
        a Bash <A
HREF="internal.html#BUILTINREF"
>builtin</A
></P
><P
><A
HREF="here-docs.html#HEREDOCREF"
><I
CLASS="FIRSTTERM"
>Here</I
>
         documents</A
>

	 <UL
><LI
><P
><A
HREF="here-docs.html#ANONHEREDOC0"
><I
CLASS="FIRSTTERM"
>Anonymous</I
>
           here documents</A
>, using <B
CLASS="COMMAND"
>:</B
></P
><P
><A
HREF="here-docs.html#CBLOCK1"
>Commenting out</A
>
	   blocks of code</P
><P
><A
HREF="here-docs.html#HSELFDOC"
>Self-documenting</A
>
	   scripts</P
></LI
><LI
><P
><A
HREF="mathc.html#BCHEREDOC"
><I
CLASS="FIRSTTERM"
>bc</I
> in a <I
CLASS="FIRSTTERM"
>here
        document</I
></A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#CATSCRIPTREF"
><I
CLASS="FIRSTTERM"
>cat</I
>
         scripts</A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#HERECS"
>Command
         substitution</A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#EXSCRIPTREF"
><I
CLASS="FIRSTTERM"
>ex</I
>
         scripts</A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#HEREFUNC"
><I
CLASS="FIRSTTERM"
>Function</I
></A
>,
	 supplying input to</P
></LI
><LI
><P
><A
HREF="here-docs.html#HERESTRINGSREF"
><I
CLASS="FIRSTTERM"
>Here</I
>
           strings</A
></P
><P
><A
HREF="here-docs.html#HSPRE"
>Prepending text</A
></P
><P
><A
HREF="here-docs.html#HSREAD"
>Using
	   <I
CLASS="FIRSTTERM"
>read</I
></A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#LIMITSTRINGREF"
><I
CLASS="FIRSTTERM"
>Limit</I
>
      string</A
></P
><P
><A
HREF="here-docs.html#INDENTEDLS"
>Closing <I
CLASS="FIRSTTERM"
>limit
            string</I
></A
> may not be indented</P
><P
><A
HREF="here-docs.html#LIMITSTRDASH"
>Dash option</A
>
           to limit string, <TT
CLASS="OPTION"
>&#60;&#60;-LimitString</TT
>
           </P
></LI
><LI
><P
><A
HREF="here-docs.html#HERELIT"
>Literal
         text output</A
>,
	 for generating program code</P
></LI
><LI
><P
><A
HREF="here-docs.html#HEREPARAMSUB"
>Parameter
           substitution</A
></P
><P
><A
HREF="here-docs.html#HEREESC"
>Disabling</A
>
	   <I
CLASS="FIRSTTERM"
>parameter substitution</I
></P
></LI
><LI
><P
><A
HREF="here-docs.html#HEREPASSP"
>Passing
         parameters</A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#HERETEMP"
>Temporary
         files</A
></P
></LI
><LI
><P
><A
HREF="here-docs.html#VIHERE"
>Using
        <I
CLASS="FIRSTTERM"
>vi</I
> non-interactively</A
></P
></LI
></UL
></P
><P
><A
HREF="histcommands.html"
>History commands</A
></P
><P
><A
HREF="variables2.html#HOMEDIRREF"
><TT
CLASS="VARNAME"
>$HOME</TT
></A
>,
         <I
CLASS="FIRSTTERM"
>user's home directory</I
></P
><P
><A
HREF="contributed-scripts.html#HOMEWORK"
>Homework assignment solver</A
></P
><P
><A
HREF="variables2.html#HOSTNAMEREF"
><TT
CLASS="VARNAME"
>$HOSTNAME</TT
></A
>,
        system <I
CLASS="FIRSTTERM"
>host name</I
></P
><P
>* * *</P
><P
><A
HREF="tests.html#IFTHEN"
>if [ condition ]; then ...</A
>
         <I
CLASS="FIRSTTERM"
>test</I
> construct
	 <UL
><LI
><P
><A
HREF="tests.html#IFGREPREF"
>if-grep</A
>,
          <I
CLASS="FIRSTTERM"
>if</I
> and <A
HREF="textproc.html#GREPREF"
>grep</A
>
          in combination</P
><P
><A
HREF="assortedtips.html#IFGREPFIX"
>Fixup</A
>
          for <I
CLASS="FIRSTTERM"
>if-grep</I
> test</P
></LI
></UL
></P
><P
><A
HREF="variables2.html#IFSREF"
><TT
CLASS="VARNAME"
>$IFS</TT
></A
>,
         <I
CLASS="FIRSTTERM"
>Internal field separator</I
> variable
	   <UL
><LI
><P
><A
HREF="variables2.html#IFSWS"
>Defaults to
        <I
CLASS="FIRSTTERM"
>whitespace</I
></A
></P
></LI
></UL
></P
><P
><A
HREF="comparison-ops.html#ICOMPARISON1"
>Integer comparison
         operators</A
></P
><P
><A
HREF="loops.html#DOINREF"
>in</A
>,
         <I
CLASS="FIRSTTERM"
>keyword</I
> preceding
         <TT
CLASS="VARNAME"
>[list]</TT
> in a <I
CLASS="FIRSTTERM"
>for</I
>
         loop</P
><P
><A
HREF="system.html#INITTABREF"
>Initialization table</A
>,
         <TT
CLASS="FILENAME"
>/etc/inittab</TT
></P
><P
><A
HREF="miscellany.html#IITEST"
>Interactive script</A
>, test for</P
><P
><A
HREF="io-redirection.html#IOREDIRREF"
>I/O redirection</A
></P
><P
><A
HREF="ivr.html#IVRREF"
>Indirect referencing of variables</A
>
         <UL
><LI
><P
><A
HREF="ivr.html#IVR2"
>New notation</A
>, introduced
         in version 2 of Bash</P
></LI
><LI
><P
><A
HREF="bash2.html#VARREFNEW"
>         Example script</A
></P
></LI
></UL
></P
><P
><A
HREF="loops.html#ITERATIONREF"
>Iteration</A
></P
><P
>* * *</P
><P
><A
HREF="internal.html#JOBIDTABLE0"
>Job IDs</A
>, table</P
><P
><A
HREF="extmisc.html#JOTREF"
>jot</A
>,
        Emit a sequence of integers. Equivalent to <A
HREF="extmisc.html#SEQREF"
>seq</A
>.
	  <UL
><LI
><P
><A
HREF="extmisc.html#JOTRANDOM"
>Random sequence
         generation</A
></P
></LI
></UL
></P
><P
>* * *</P
><P
><A
HREF="internal.html#KEYWORDREF"
>Keywords</A
></P
><P
><A
HREF="internal.html#KILLREF"
>kill</A
>,
        terminate a process by <A
HREF="special-chars.html#PROCESSIDDEF"
>process ID</A
>
	  <UL
><LI
><P
><A
HREF="internal.html#ZOMBIEREF"
>Options</A
> (<TT
CLASS="OPTION"
>-l</TT
>,
	<TT
CLASS="OPTION"
>-9</TT
>)</P
></LI
></UL
></P
><P
><A
HREF="internal.html#KILLALLREF"
>killall</A
>,
        terminate a process <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>by name</I
></SPAN
></P
><P
><A
HREF="system.html#KILLALL2REF"
><I
CLASS="FIRSTTERM"
>killall
         script</I
></A
> in <TT
CLASS="FILENAME"
>/etc/rc.d/init.d</TT
></P
><P
>* * *</P
><P
><A
HREF="comparison-ops.html#LE0REF"
> -le </A
>,
         <I
CLASS="FIRSTTERM"
>less-than or equal</I
>
	 <A
HREF="comparison-ops.html#ICOMPARISON1"
>integer comparison</A
> test</P
><P
><A
HREF="internal.html#LETREF"
>let</A
>,
        setting and carrying out arithmetic operations on variables</P
><P
><A
HREF="here-docs.html#LIMITSTRINGREF"
>Limit string</A
>,
         in a <A
HREF="here-docs.html#HEREDOCREF"
>here document</A
></P
><P
><A
HREF="variables2.html#LINENOREF"
><TT
CLASS="VARNAME"
>$LINENO</TT
></A
>,
         variable indicating the <I
CLASS="FIRSTTERM"
>line number</I
> where
         it appears in a script</P
><P
><A
HREF="external.html#LINKREF"
>Link</A
>, file
         (using <I
CLASS="FIRSTTERM"
>ln</I
> command)
	     <UL
><LI
><P
><A
HREF="external.html#LINKMINVOK"
>Invoking script with multiple names</A
>,
          using <I
CLASS="FIRSTTERM"
>ln</I
></P
></LI
><LI
><P
><A
HREF="external.html#SYMLINKREF"
><I
CLASS="FIRSTTERM"
>symbolic</I
>
	  links</A
>, <I
CLASS="FIRSTTERM"
>ln -s </I
></P
></LI
></UL
></P
><P
><A
HREF="list-cons.html#LISTCONSREF"
>List constructs</A
>
        <UL
><LI
><P
><A
HREF="list-cons.html#LCONS1"
><I
CLASS="FIRSTTERM"
>And</I
>
        list</A
></P
></LI
><LI
><P
><A
HREF="list-cons.html#ORLISTREF"
><I
CLASS="FIRSTTERM"
>Or</I
>
        list</A
></P
></LI
></UL
></P
><P
><A
HREF="localvar.html#LOCALREF1"
>Local variables</A
>
         <UL
><LI
><P
>and <A
HREF="localvar.html#LOCVARRECUR"
>recursion</A
></P
></LI
></UL
></P
><P
><A
HREF="localization.html"
>Localization</A
></P
><P
><A
HREF="operations.html#LOGOPS1"
>Logical operators</A
>
         (<TT
CLASS="VARNAME"
>&#38;&#38;</TT
>, <TT
CLASS="VARNAME"
>||</TT
>,
         etc.)</P
><P
><A
HREF="files.html#LOGOUTFILEREF1"
>Logout file</A
>,
         the <TT
CLASS="FILENAME"
>~/.bash_logout</TT
> file</P
><P
><A
HREF="loops.html#LOOPS1"
>Loops</A
>
        <UL
><LI
><P
><A
HREF="loopcontrol.html#BRKCONT1"
>break</A
>
         loop control command</P
></LI
><LI
><P
><A
HREF="loopcontrol.html#BRKCONT1"
>continue</A
> loop
        control command</P
></LI
><LI
><P
><I
CLASS="FIRSTTERM"
>C</I
>-style
	loop within <A
HREF="dblparens.html#DBLPARENSREF"
>double
	parentheses</A
></P
><P
><A
HREF="loops.html#LOOPCSTYLE"
><I
CLASS="FIRSTTERM"
>for</I
> loop</A
></P
><P
><A
HREF="loops.html#WLOOPCSTYLE"
><I
CLASS="FIRSTTERM"
>while</I
> loop</A
></P
></LI
><LI
><P
><A
HREF="loops.html#DOINREF"
>do</A
> (keyword),
         begins execution of commands within a loop</P
></LI
><LI
><P
><A
HREF="loops.html#DOINREF"
>done</A
> (keyword),
         terminates a loop</P
></LI
><LI
><P
><A
HREF="loops.html#FORLOOPREF1"
><I
CLASS="FIRSTTERM"
>for</I
>
           loops</A
></P
><P
><TT
CLASS="REPLACEABLE"
><I
>for</I
></TT
> <TT
CLASS="VARNAME"
>arg</TT
>
          <TT
CLASS="REPLACEABLE"
><I
>in</I
></TT
> <TT
CLASS="VARNAME"
>[list]</TT
>;
          <TT
CLASS="REPLACEABLE"
><I
>do</I
></TT
></P
><P
><A
HREF="loops.html#LOOPCS"
><I
CLASS="FIRSTTERM"
>Command
	  substitution</I
> to generate
	  <TT
CLASS="VARNAME"
>[list]</TT
></A
></P
><P
><A
HREF="loops.html#LIGLOB"
>Filename expansion
	  in <TT
CLASS="VARNAME"
>[list]</TT
></A
></P
><P
><A
HREF="loops.html#MULTPARAML"
>Multiple parameters
	  in each <TT
CLASS="VARNAME"
>[list]</TT
> element</A
></P
><P
><A
HREF="loops.html#OMITLIST"
>Omitting
	  <TT
CLASS="VARNAME"
>[list]</TT
></A
>, defaults to
	  <A
HREF="variables2.html#POSPARAMREF"
>positional parameters</A
></P
><P
><A
HREF="loops.html#PARAMLI"
>Parameterizing
	   <TT
CLASS="VARNAME"
>[list]</TT
></A
></P
><P
><A
HREF="loops.html#LOOPREDIR"
>Redirection</A
></P
></LI
><LI
><P
><A
HREF="loops.html#DOINREF"
>in</A
>,
         (keyword) preceding [list] in a
         <I
CLASS="FIRSTTERM"
>for</I
> loop</P
></LI
><LI
><P
><A
HREF="nestedloops.html"
>Nested
         loops</A
></P
></LI
><LI
><P
><A
HREF="special-chars.html#BGLOOP0"
>Running a
         loop <SPAN
CLASS="emphasis"
><I
CLASS="EMPHASIS"
>in the background</I
></SPAN
></A
>,
	 <I
CLASS="FIRSTTERM"
>script example</I
></P
></LI
><LI
><P
>Semicolon required, when <I
CLASS="FIRSTTERM"
>do</I
> is on first line
	  of loop</P
><P
><A
HREF="loops.html#NEEDSEMICOLON"
><I
CLASS="FIRSTTERM"
>for</I
>
	  loop</A
></P
><P
><A
HREF="loops.html#WHILENEEDSEMI"
><I
CLASS="FIRSTTERM"
>while</I
>
	  loop</A
></P
></LI
><LI
><P
><A
HREF="loops.html#UNTILLOOPREF"
>until</A
> loop</P
><P
><TT
CLASS="REPLACEABLE"
><I
>until [ condition-is-true ]; do</I
></TT
>
	 </P
></LI
><LI
><P
><A
HREF="loops.html#WHILELOOPREF"
>while</A
>
        loop</P
><P
><TT
CLASS="REPLACEABLE"
><I
>while [ condition ]; do</I
></TT
></P
><P
><A
HREF="loops.html#WHILEFUNC"
>Function call</A
>
	  inside test brackets</P
><P
><A
HREF="loops.html#WHMULTCOND"
>Multiple conditions</A
></P
><P
><A
HREF="loops.html#WHILENOBRACKETS"
>Omitting <I
CLASS="FIRSTTERM"
>test
	  brackets</I
></A
></P
><P
><A
HREF="loops.html#WHREDIR"
>Redirection</A
></P
><P
><A
HREF="loops.html#WHILEREADREF2"
>         <I
CLASS="FIRSTTERM"
>while read</I
></A
> construct</P
></LI
><LI
><P
><A
HREF="loops.html#CHOOSELOOP"
>Which type of loop to
        use</A
></P
></LI
></UL
></P
><P
>Loopback devices
         <UL
><LI
><P
><A
HREF="devproc.html#LOOPBACKREF"
>In <TT
CLASS="FILENAME"
>/dev</TT
> directory</A
></P
></LI
><LI
><P
><A
HREF="system.html#ISOMOUNTREF0"
>Mounting an ISO image</A
></P
></LI
></UL
></P
><P
><A
HREF="comparison-ops.html#LT0REF"
> -lt </A
>,
         <I
CLASS="FIRSTTERM"
>less-than</I
> <A
HREF="comparison-ops.html#ICOMPARISON1"
>integer
	 comparison</A
> test</P
><P
>* * *</P
><P
><A
HREF="extmisc.html#M4REF"
>m4</A
>, macro processing language</P
><P
><A
HREF="variables2.html#MACHTYPEREF"
><TT
CLASS="VARNAME"
>$MACHTYPE</TT
></A
>,
         <I
CLASS="FIRSTTERM"
>Machine type</I
></P
><P
><A
HREF="sha-bang.html#MAGNUMREF"
>Magic number</A
>,
         marker at the head of a file indicating the file type</P
><P
><A
HREF="filearchiv.html#MAKEFILEREF"
><TT
CLASS="FILENAME"
>Makefile</TT
></A
>,
         file containing the list of dependencies used by <A
HREF="filearchiv.html#MAKEREF"
>make</A
> command</P
><P
><A
HREF="regexp.html#METAMEANINGREF"
>meta-meaning</A
></P
><P
><A
HREF="operations.html#MODULOREF"
>Modulo</A
>, arithmetic
         <I
CLASS="FIRSTTERM"
>remainder</I
> operator
	    <UL
><LI
><P
>Application: <A
HREF="contributed-scripts.html#PRIMES1"
>Generating
            prime numbers</A
></P
></LI
></UL
></P
><P
><A
HREF="mathc.html#MONTHLYPMT0"
>Mortgage calculations</A
>,
        <I
CLASS="FIRSTTERM"
>example script</I
></P
><P
>* * *</P
><P
><B
CLASS="COMMAND"
>-n </B
>
        <A
HREF="comparison-ops.html#STRINGNOTNULL"
>String not
        <I
CLASS="FIRSTTERM"
>null</I
></A
> test</P
><P
><A
HREF="extmisc.html#NAMEDPIPEREF"
>Named pipe</A
>, a temporary
         FIFO buffer
	 <UL
><LI
><P
><A
HREF="contributed-scripts.html#ZFIFO"
><I
CLASS="FIRSTTERM"
>Example
         script</I
></A
></P
></LI
></UL
></P
><P
><A
HREF="system.html#NCREF"
>nc</A
>, <I
CLASS="FIRSTTERM"
>netcat</I
>,
        a toolkit for TCP and UDP ports</P
><P
><A
HREF="comparison-ops.html#NEQUALREF"
>-ne</A