[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Changes to grep/manual/grep.html,v
|
From: |
Jim Meyering |
|
Subject: |
Changes to grep/manual/grep.html,v |
|
Date: |
Fri, 22 Apr 2016 05:25:57 +0000 |
CVSROOT: /webcvs/grep
Module name: grep
Changes by: Jim Meyering <meyering> 16/04/22 05:25:56
Index: grep.html
===================================================================
RCS file: /webcvs/grep/grep/manual/grep.html,v
retrieving revision 1.23
retrieving revision 1.24
diff -u -b -r1.23 -r1.24
--- grep.html 11 Mar 2016 06:09:07 -0000 1.23
+++ grep.html 22 Apr 2016 05:25:45 -0000 1.24
@@ -13,10 +13,10 @@
"GNU Free Documentation License". -->
<!-- Created by GNU Texinfo 6.0, http://www.gnu.org/software/texinfo/ -->
<head>
-<title>GNU Grep 2.24</title>
+<title>GNU Grep 2.25</title>
-<meta name="description" content="GNU Grep 2.24">
-<meta name="keywords" content="GNU Grep 2.24">
+<meta name="description" content="GNU Grep 2.25">
+<meta name="keywords" content="GNU Grep 2.25">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
@@ -59,7 +59,7 @@
</head>
<body lang="en">
-<h1 class="settitle" align="center">GNU Grep 2.24</h1>
+<h1 class="settitle" align="center">GNU Grep 2.25</h1>
@@ -123,7 +123,7 @@
<p><code>grep</code> prints lines that contain a match for a pattern.
</p>
-<p>This manual is for version 2.24 of GNU Grep.
+<p>This manual is for version 2.25 of GNU Grep.
</p>
<p>This manual is for <code>grep</code>, a pattern matching engine.
</p>
@@ -303,8 +303,8 @@
<a name="index-_002d_002dregexp_003dpattern"></a>
<a name="index-pattern-list"></a>
<p>Use <var>pattern</var> as the pattern.
-This can be used to specify multiple search patterns,
-or to protect a pattern beginning with a ‘<samp>-</samp>’.
+If this option is used multiple times or is combined with the
+<samp>-f</samp> (<samp>--file</samp>) option, search for all patterns given.
(<samp>-e</samp> is specified by POSIX.)
</p>
</dd>
@@ -314,6 +314,8 @@
<a name="index-_002d_002dfile"></a>
<a name="index-pattern-from-file"></a>
<p>Obtain patterns from <var>file</var>, one per line.
+If this option is used multiple times or is combined with the
+<samp>-e</samp> (<samp>--regexp</samp>) option, search for all patterns given.
The empty file contains zero patterns, and therefore matches nothing.
(<samp>-f</samp> is specified by POSIX.)
</p>
@@ -768,17 +770,13 @@
indicate that the file contains binary data,
assume that the file is of type <var>type</var>.
Non-text bytes indicate binary data; these are either output bytes that are
-improperly encoded for the current locale, or null input bytes when the
+improperly encoded for the current locale (see <a
href="#Environment-Variables">Environment Variables</a>), or null input bytes
when the
<samp>-z</samp> (<samp>--null-data</samp>) option is not given (see <a
href="#Other-Options">Other Options</a>).
</p>
<p>By default, <var>type</var> is ‘<samp>binary</samp>’, and when
<code>grep</code>
discovers that a file is binary it suppresses any further output, and
instead outputs either a one-line message saying that a binary file
matches, or no message if there is no match.
-When processing binary data, <code>grep</code> may treat non-text bytes
-as line terminators; for example, the pattern ‘<samp>.</samp>’
(period) might
-not match a null byte, as the null byte might be treated as a line
-terminator even without the <samp>-z</samp> (<samp>--null-data</samp>) option.
</p>
<p>If <var>type</var> is ‘<samp>without-match</samp>’,
when <code>grep</code> discovers that a file is binary
@@ -789,10 +787,23 @@
<code>grep</code> processes a binary file as if it were text;
this is equivalent to the <samp>-a</samp> option.
</p>
-<p><em>Warning:</em> ‘<samp>--binary-files=text</samp>’ might
output binary garbage,
-which can have nasty side effects
-if the output is a terminal and
-if the terminal driver interprets some of it as commands.
+<p>When <var>type</var> is ‘<samp>binary</samp>’,
<code>grep</code> may treat non-text
+bytes as line terminators even without the <samp>-z</samp>
+(<samp>--null-data</samp>) option. This means choosing
‘<samp>binary</samp>’
+versus ‘<samp>text</samp>’ can affect whether a pattern matches a
file. For
+example, when <var>type</var> is ‘<samp>binary</samp>’ the pattern
‘<samp>q$</samp>’ might
+match ‘<samp>q</samp>’ immediately followed by a null byte, even
though this
+is not matched when <var>type</var> is ‘<samp>text</samp>’.
Conversely, when
+<var>type</var> is ‘<samp>binary</samp>’ the pattern
‘<samp>.</samp>’ (period) might not
+match a null byte.
+</p>
+<p><em>Warning:</em> The <samp>-a</samp> (<samp>--binary-files=text</samp>)
option
+might output binary garbage, which can have nasty side effects if the
+output is a terminal and if the terminal driver interprets some of it
+as commands. On the other hand, when reading files whose text
+encodings are unknown, it can be helpful to use <samp>-a</samp> or to set
+‘<samp>LC_ALL='C'</samp>’ in the environment, in order to find
more matches
+even if the matches are unsafe for direct display.
</p>
</dd>
<dt><samp>-D <var>action</var></samp></dt>
@@ -947,8 +958,8 @@
<dd><a name="index-_002dz"></a>
<a name="index-_002d_002dnull_002ddata"></a>
<a name="index-zero_002dterminated-lines"></a>
-<p>Treat the input as a set of lines, each terminated by a zero byte (the
-ASCII NUL character) instead of a newline.
+<p>Treat input and output data as sequences of lines, each terminated by
+a zero byte (the ASCII NUL character) instead of a newline.
Like the <samp>-Z</samp> or <samp>--null</samp> option,
this option can be used with commands like
‘<samp>sort -z</samp>’ to process arbitrary file names.
@@ -989,6 +1000,7 @@
if the locale catalog is not installed,
or if <code>grep</code> was not compiled
with national language support (NLS).
+The shell command <code>locale -a</code> lists locales that are currently
available.
</p>
<p>Many of the environment variables in the following list let you
control highlighting using
@@ -1204,6 +1216,10 @@
<p>These variables specify the locale for the <code>LC_CTYPE</code> category,
which determines the type of characters,
e.g., which characters are whitespace.
+This category also determines the character encoding, that is, whether
+text is encoded in UTF-8, ASCII, or some other encoding. In the
+‘<samp>C</samp>’ or ‘<samp>POSIX</samp>’ locale, all
characters are encoded as a
+single byte and every byte is a valid character.
</p>
</dd>
<dt><code>LANGUAGE</code></dt>
@@ -1325,8 +1341,8 @@
<dt><samp>--perl-regexp</samp></dt>
<dd><a name="index-_002dP"></a>
<a name="index-_002d_002dperl_002dregexp"></a>
-<a name="index-matching-Perl-regular-expressions"></a>
-<p>Interpret the pattern as a Perl regular expression.
+<a name="index-matching-Perl_002dcompatible-regular-expressions"></a>
+<p>Interpret the pattern as a Perl-compatible regular expression (PCRE).
This is highly experimental and
‘<samp>grep -P</samp>’ may warn of unimplemented features.
</p>
@@ -1358,16 +1374,16 @@
by using various operators to combine smaller expressions.
<code>grep</code> understands
three different versions of regular expression syntax:
-“basic,” (BRE) “extended” (ERE) and “perl”.
+“basic” (BRE), “extended” (ERE) and “perl”
(PCRE).
In GNU <code>grep</code>,
there is no difference in available functionality between the basic and
extended syntaxes.
In other implementations, basic regular expressions are less powerful.
The following description applies to extended regular expressions;
differences for basic regular expressions are summarized afterwards.
-Perl regular expressions give additional functionality, and are
-documented in the <i>pcresyntax</i>(3) and <i>pcrepattern</i>(3) manual pages,
-but work only if PCRE is available in the system.
+Perl-compatible regular expressions give additional functionality, and
+are documented in the <i>pcresyntax</i>(3) and <i>pcrepattern</i>(3) manual
+pages, but work only if PCRE is available in the system.
</p>
<table class="menu" border="0" cellspacing="0">
<tr><td align="left" valign="top">• <a href="#Fundamental-Structure"
accesskey="1">Fundamental Structure</a>:</td><td> </td><td
align="left" valign="top">
@@ -2911,7 +2927,7 @@
<tr><td></td><td valign="top"><a
href="#index-matching-basic-regular-expressions">matching basic regular
expressions</a>:</td><td> </td><td valign="top"><a
href="#grep-Programs">grep Programs</a></td></tr>
<tr><td></td><td valign="top"><a
href="#index-matching-extended-regular-expressions">matching extended regular
expressions</a>:</td><td> </td><td valign="top"><a
href="#grep-Programs">grep Programs</a></td></tr>
<tr><td></td><td valign="top"><a href="#index-matching-fixed-strings">matching
fixed strings</a>:</td><td> </td><td valign="top"><a
href="#grep-Programs">grep Programs</a></td></tr>
-<tr><td></td><td valign="top"><a
href="#index-matching-Perl-regular-expressions">matching Perl regular
expressions</a>:</td><td> </td><td valign="top"><a
href="#grep-Programs">grep Programs</a></td></tr>
+<tr><td></td><td valign="top"><a
href="#index-matching-Perl_002dcompatible-regular-expressions">matching
Perl-compatible regular expressions</a>:</td><td> </td><td valign="top"><a
href="#grep-Programs">grep Programs</a></td></tr>
<tr><td></td><td valign="top"><a href="#index-matching-whole-words">matching
whole words</a>:</td><td> </td><td valign="top"><a
href="#Matching-Control">Matching Control</a></td></tr>
<tr><td></td><td valign="top"><a
href="#index-max_002dcount">max-count</a>:</td><td> </td><td
valign="top"><a href="#General-Output-Control">General Output
Control</a></td></tr>
<tr><td></td><td valign="top"><a
href="#index-mc-GREP_005fCOLORS-capability"><code>mc GREP_COLORS <span
class="roman">capability</span></code></a>:</td><td> </td><td
valign="top"><a href="#Environment-Variables">Environment
Variables</a></td></tr>
| [Prev in Thread] |
Current Thread |
[Next in Thread] |
- Changes to grep/manual/grep.html,v,
Jim Meyering <=