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author | Denis Vlasenko | 2007-11-13 17:13:31 +0000 |
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committer | Denis Vlasenko | 2007-11-13 17:13:31 +0000 |
commit | 72cc9641f80b6981cc97fd66feb8d5842ea5ed03 (patch) | |
tree | c8bb972fb90b451faae4dfe60cd3f33a77d40bff /editors/sed_summary.htm | |
parent | 40276648ab31822068c3408ae43a5ecaafd03a5c (diff) | |
download | busybox-72cc9641f80b6981cc97fd66feb8d5842ea5ed03.zip busybox-72cc9641f80b6981cc97fd66feb8d5842ea5ed03.tar.gz |
add sed mini-doc
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diff --git a/editors/sed_summary.htm b/editors/sed_summary.htm new file mode 100644 index 0000000..4ac9b16 --- /dev/null +++ b/editors/sed_summary.htm @@ -0,0 +1,220 @@ +<html> + +<head><title>Command Summary for sed (sed & awk, Second Edition)</title> +</head> + +<body> + +<h2>Command Summary for sed</h2> + +<dl> + +<dt><b>: </b> <b> :</b><em>label</em></dt> +<dd>Label a line in the script for the transfer of control by +<b>b</b> or <b>t</b>. +<em>label</em> may contain up to seven characters. +(The POSIX standard says that an implementation can allow longer +labels if it wishes to. GNU sed allows labels to be of any length.) +</p></dd> + + +<dt><b>=</b> [<em>address</em>]<b>=</b></dt> +<dd>Write to standard output the line number of addressed line.</p></dd> + + +<dt><b>a</b> [<em>address</em>]<b>a\</b></dt> +<dd><em>text</em></p> + +<p>Append <em>text</em> +following each line matched by <em>address</em>. If +<em>text</em> goes over more than one line, newlines +must be "hidden" by preceding them with a backslash. The +<em>text</em> will be terminated by the first +newline that is not hidden in this way. The +<em>text</em> is not available in the pattern space +and subsequent commands cannot be applied to it. The results of this +command are sent to standard output when the list of editing commands +is finished, regardless of what happens to the current line in the +pattern space.</p></dd> + + +<dt><b>b</b> [<em>address1</em>[,<em>address2</em>]]<b>b</b>[<em>label</em>]</dt> +<dd>Transfer control unconditionally (branch) to +<b>:</b><em>label</em> elsewhere in +script. That is, the command following the +<em>label</em> is the next command applied to the +current line. If no <em>label</em> is specified, +control falls through to the end of the script, so no more commands +are applied to the current line.</p></dd> + + +<dt><b>c</b> [<em>address1</em>[,<em>address2</em>]]<b>c\</b></dt> +<dd><em>text</em></p> + +<p>Replace (change) the lines selected by the address with +<em>text</em>. When a range of lines is specified, +all lines as a group are replaced by a single copy of +<em>text</em>. The newline following each line of +<em>text</em> must be escaped by a backslash, except +the last line. The contents of the pattern space are, in effect, +deleted and no subsequent editing commands can be applied to it (or to +<em>text</em>).</p></dd> + + +<dt><b>d</b> [<em>address1</em>[,<em>address2</em>]]<b>d</b></dt> +<dd>Delete line(s) from pattern space. Thus, the line is not passed to standard +output. A new line of input is read and editing resumes with first +command in script.</p></dd> + + +<dt><b>D</b> [<em>address1</em>[,<em>address2</em>]]<b>D</b></dt> +<dd>Delete first part (up to embedded newline) of multiline pattern space created +by <b>N</b> command and resume editing with first command in +script. If this command empties the pattern space, then a new line +of input is read, as if the <b>d</b> command had been executed.</p></dd> + + +<dt><b>g</b> [<em>address1</em>[,<em>address2</em>]]<b>g</b></dt> +<dd>Copy (get) contents of hold space (see <b>h</b> or +<b>H</b> command) into the pattern space, wiping out +previous contents.</p></dd> + + +<dt><b>G</b> [<em>address1</em>[,<em>address2</em>]]<b>G</b></dt> +<dd>Append newline followed by contents of hold space (see +<b>h</b> or <b>H</b> command) to contents of +the pattern space. If hold space is empty, a newline is still +appended to the pattern space.</p></dd> + + +<dt><b>h</b> [<em>address1</em>[,<em>address2</em>]]<b>h</b></dt> +<dd>Copy pattern space into hold space, a special temporary buffer. +Previous contents of hold space are wiped out.</p></dd> + + +<dt><b>H</b> [<em>address1</em>[,<em>address2</em>]]<b>H</b></dt> +<dd>Append newline and contents of pattern space to contents of the hold +space. Even if hold space is empty, this command still appends the +newline first.</p></dd> + + +<dt><b>i</b> [<em>address1</em>]<b>i\</b></dt> +<dd><em>text</em></p> + +<p>Insert <em>text</em> before each line matched by +<em>address</em>. (See <b>a</b> for +details on <em>text</em>.)</p></dd> + + +<dt><b>l</b> [<em>address1</em>[,<em>address2</em>]]<b>l</b></dt> +<dd>List the contents of the pattern space, showing nonprinting characters +as ASCII codes. Long lines are wrapped.</p></dd> + + +<dt><b>n</b> [<em>address1</em>[,<em>address2</em>]]<b>n</b></dt> +<dd>Read next line of input into pattern space. Current line is sent to +standard output. New line becomes current line and increments line +counter. Control passes to command following <b>n</b> +instead of resuming at the top of the script.</p></dd> + + +<dt><b>N</b> [<em>address1</em>[,<em>address2</em>]]<b>N</b></dt> +<dd>Append next input line to contents of pattern space; the new line is +separated from the previous contents of the pattern space by a newline. +(This command is designed to allow pattern matches across two +lines. Using \n to match the embedded newline, you can match +patterns across multiple lines.)</p></dd> + + +<dt><b>p</b> [<em>address1</em>[,<em>address2</em>]]<b>p</b></dt> +<dd>Print the addressed line(s). Note that this can result in duplicate +output unless default output is suppressed by using "#n" or +the <span class="option">-n</span> + +command-line option. Typically used before commands that change flow +control (<b>d</b>, <b>n</b>, +<b>b</b>) and might prevent the current line from being +output.</p></dd> + + +<dt><b>P</b> [<em>address1</em>[,<em>address2</em>]]<b>P</b></dt> +<dd>Print first part (up to embedded newline) of multiline pattern space +created by <b>N</b> command. Same as <b>p</b> +if <b>N</b> has not been applied to a line.</p></dd> + + +<dt><b>q</b> [<em>address</em>]<b>q</b></dt> +<dd>Quit when <em>address</em> is encountered. The +addressed line is first written to output (if default output is not +suppressed), along with any text appended to it by previous +<b>a</b> or <b>r</b> commands.</p></dd> + + +<dt><b>r</b> [<em>address</em>]<b>r</b> <em>file</em></dt> +<dd>Read contents of <em>file</em> and append after the +contents of the pattern space. Exactly one space must be put between +<b>r</b> and the filename.</p></dd> + + +<dt><b>s</b> [<em>address1</em>[,<em>address2</em>]]<b>s</b>/<em>pattern</em>/<em>replacement</em>/[<em>flags</em>]</dt> +<dd>Substitute <em>replacement</em> for +<em>pattern</em> on each addressed line. If pattern +addresses are used, the pattern <b>//</b> represents the +last pattern address specified. The following flags can be specified:</p> + + <dl> + + <dt><b>n</b></dt> + <dd>Replace <em>n</em>th instance of + /<em>pattern</em>/ on each addressed line. + <em>n</em> is any number in the range 1 to 512, and + the default is 1.</p></dd> + + <dt><b>g</b></dt> + <dd>Replace all instances of /<em>pattern</em>/ on each + addressed line, not just the first instance.</p></dd> + + <dt><b>p</b></dt> + <dd>Print the line if a successful substitution is done. If several + successful substitutions are done, multiple copies of the line will be + printed.</p></dd> + + <dt><b>w</b> <em>file</em></dt> + <dd>Write the line to <em>file</em> if a replacement + was done. A maximum of 10 different <em>files</em> can be opened.</p></dd> + + </dl> + +</dd> + + +<dt><b>t</b> [<em>address1</em>[,<em>address2</em>]]<b>t </b>[<em>label</em>]</dt> +<dd>Test if successful substitutions have been made on addressed lines, +and if so, branch to line marked by :<em>label</em>. +(See <b>b</b> and <b>:</b>.) If label is not +specified, control falls through to bottom of script.</p></dd> + + +<dt><b>w</b> [<em>address1</em>[,<em>address2</em>]]<b>w</b> <em>file</em></dt> +<dd>Append contents of pattern space to <em>file</em>. +This action occurs when the command is encountered rather than when +the pattern space is output. Exactly one space must separate the +<b>w</b> and the filename. A maximum of 10 different +files can be opened in a script. This command will create the file if +it does not exist; if the file exists, its contents will be +overwritten each time the script is executed. Multiple write commands +that direct output to the same file append to the end of the file.</p></dd> + + +<dt><b>x</b> [<em>address1</em>[,<em>address2</em>]]<b>x</b></dt> +<dd>Exchange contents of the pattern space with the contents of the hold +space.</p></dd> + + +<dt><b>y</b> [<em>address1</em>[,<em>address2</em>]]<b>y</b>/<em>abc</em>/<em>xyz</em>/</dt> +<dd>Transform each character by position in string +<em>abc</em> to its equivalent in string +<em>xyz</em>.</p></dd> + + +</dl> |