Merging upstream version 1.7.

Signed-off-by: Daniel Baumann <daniel@debian.org>

ChangeLog

@@ -1,3 +1,9 @@
+2018-02-13  Antonio Diaz Diaz  <antonio@gnu.org>
+
+	* Version 1.7 released.
+	* zgrep.cc (main): Pass '--color' option to grep.
+	* check.sh: Added new tests for zgrep.
+
 2017-04-05  Antonio Diaz Diaz  <antonio@gnu.org>
 
 	* Version 1.6 released.
@@ -12,7 +18,7 @@
 	* zdiff.cc (set_fifonames): Use '_' if both names are different.
 	* configure: Avoid warning on some shells when testing for g++.
 	* Makefile.in: Detect the existence of install-info.
-	* testsuite/check.sh: A POSIX shell is required to run the tests.
+	* check.sh: A POSIX shell is required to run the tests.
 
 2015-05-29  Antonio Diaz Diaz  <antonio@gnu.org>
 
@@ -25,7 +31,7 @@
 2014-08-30  Antonio Diaz Diaz  <antonio@gnu.org>
 
 	* Version 1.3 released.
-	* testsuite/check.sh: Fixed two values of expected exit status.
+	* check.sh: Fixed two values of expected exit status.
 	* zutils.texi: Documented that '--format' does not verify format.
 	* Added two missing #includes.
 	* License changed to GPL version 2 or later.
@@ -88,7 +94,7 @@
 	  documentation because egrep and fgrep are deprecated.
 	* ztest.cc: New file implementing ztest functionality in C++.
 	* Makefile.in: Added quotes to directory names.
-	* testsuite/check.sh: Use 'test.txt' instead of 'COPYING' for testing.
+	* check.sh: Use 'test.txt' instead of 'COPYING' for testing.
 	* Removed environment safeguards from configure as requested by
 	  Richard Stallman. Now environment variables affect configure.
 
@@ -134,7 +140,7 @@
 	* Version 0.1 released.
 
 
-Copyright (C) 2009-2017 Antonio Diaz Diaz.
+Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
 This file is a collection of facts, and thus it is not copyrightable,
 but just in case, you have unlimited permission to copy, distribute and

INSTALL

@@ -70,7 +70,7 @@ After running 'configure', you can run 'make' and 'make install' as
 explained above.
 
 
-Copyright (C) 2009-2017 Antonio Diaz Diaz.
+Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
 This file is free documentation: you have unlimited permission to copy,
 distribute and modify it.

NEWS

@@ -1,6 +1,4 @@
-Changes in version 1.6:
+Changes in version 1.7:
 
-zcmp now accepts the 'B' suffix in the values of '--ignore-initial' as
+zgrep now passes the '--color' option to grep. (But it only works if the
-in '--ignore-initial=1kB:1234B'.
+grep program used supports it).
-
-The input filename is now shown in more error messages.

README

@@ -1,13 +1,13 @@
 Description
 
-Zutils is a collection of utilities able to deal with any combination of
+Zutils is a collection of utilities able to process any combination of
 compressed and uncompressed files transparently. If any given file,
 including standard input, is compressed, its decompressed content is
 used. Compressed files are decompressed on the fly; no temporary files
 are created.
 
 These utilities are not wrapper scripts but safer and more efficient C++
-programs. In particular the "--recursive" option is very efficient in
+programs. In particular the '--recursive' option is very efficient in
 those utilities supporting it.
 
 The provided utilities are zcat, zcmp, zdiff, zgrep, ztest and zupdate.
@@ -23,21 +23,21 @@ NOTE: Bzip2 and lzip provide well-defined values of exit status, which
 makes them safe to use with zutils. Gzip and xz may return ambiguous
 warning values, making them less reliable back ends for zutils.
 
-FORMAT NOTE 1: The "--format" option allows the processing of a subset
+FORMAT NOTE 1: The '--format' option allows the processing of a subset
 of formats in recursive mode and when trying compressed file names:
-"zgrep foo -r --format=bz2,lz somedir somefile.tar".
+'zgrep foo -r --format=bz2,lz somedir somefile.tar'.
 
-FORMAT NOTE 2: If the "--force-format" option is given, the files are
+FORMAT NOTE 2: If the '--force-format' option is given, the files are
 passed to the corresponding decompressor without verifying their format,
 allowing for example the processing of compress'd (.Z) files with gzip:
-"zcmp --force-format=gz file.Z file.lz".
+'zcmp --force-format=gz file.Z file.lz'.
 
 LANGUAGE NOTE: Uncompressed = not compressed = plain data; it may never
 have been compressed. Decompressed is used to refer to data which have
 undergone the process of decompression.
 
 
-Copyright (C) 2009-2017 Antonio Diaz Diaz.
+Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
 This file is free documentation: you have unlimited permission to copy,
 distribute and modify it.

arg_parser.cc

@@ -1,5 +1,5 @@
 /*  Arg_parser - POSIX/GNU command line argument parser. (C++ version)
-    Copyright (C) 2006-2017 Antonio Diaz Diaz.
+    Copyright (C) 2006-2018 Antonio Diaz Diaz.
 
     This library is free software. Redistribution and use in source and
     binary forms, with or without modification, are permitted provided

arg_parser.h

@@ -1,5 +1,5 @@
 /*  Arg_parser - POSIX/GNU command line argument parser. (C++ version)
-    Copyright (C) 2006-2017 Antonio Diaz Diaz.
+    Copyright (C) 2006-2018 Antonio Diaz Diaz.
 
     This library is free software. Redistribution and use in source and
     binary forms, with or without modification, are permitted provided

configure

@@ -1,12 +1,12 @@
 #! /bin/sh
 # configure script for Zutils - Utilities dealing with compressed files
-# Copyright (C) 2009-2017 Antonio Diaz Diaz.
+# Copyright (C) 2009-2018 Antonio Diaz Diaz.
 #
 # This configure script is free software: you have unlimited permission
 # to copy, distribute and modify it.
 
 pkgname=zutils
-pkgversion=1.6
+pkgversion=1.7
 srctrigger=doc/${pkgname}.texi
 
 # clear some things potentially inherited from environment.
@@ -180,7 +180,7 @@ echo "GREP = ${GREP}"
 rm -f Makefile
 cat > Makefile << EOF
 # Makefile for Zutils - Utilities dealing with compressed files
-# Copyright (C) 2009-2017 Antonio Diaz Diaz.
+# Copyright (C) 2009-2018 Antonio Diaz Diaz.
 # This file was generated automatically by configure. Don't edit.
 #
 # This Makefile is free software: you have unlimited permission

doc/zcat.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.46.1.
-.TH ZCAT "1" "April 2017" "zcat (zutils) 1.6" "User Commands"
+.TH ZCAT "1" "February 2018" "zcat (zutils) 1.7" "User Commands"
 .SH NAME
 zcat \- decompress and concatenate files to standard output
 .SH SYNOPSIS
@@ -88,7 +88,7 @@ Report bugs to zutils\-bug@nongnu.org
 .br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2017 Antonio Diaz Diaz.
+Copyright \(co 2018 Antonio Diaz Diaz.
 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
 .br
 This is free software: you are free to change and redistribute it.

doc/zcmp.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.46.1.
-.TH ZCMP "1" "April 2017" "zcmp (zutils) 1.6" "User Commands"
+.TH ZCMP "1" "February 2018" "zcmp (zutils) 1.7" "User Commands"
 .SH NAME
 zcmp \- decompress and compare two files byte by byte
 .SH SYNOPSIS
@@ -85,7 +85,7 @@ Report bugs to zutils\-bug@nongnu.org
 .br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2017 Antonio Diaz Diaz.
+Copyright \(co 2018 Antonio Diaz Diaz.
 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
 .br
 This is free software: you are free to change and redistribute it.

doc/zdiff.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.46.1.
-.TH ZDIFF "1" "April 2017" "zdiff (zutils) 1.6" "User Commands"
+.TH ZDIFF "1" "February 2018" "zdiff (zutils) 1.7" "User Commands"
 .SH NAME
 zdiff \- decompress and compare two files line by line
 .SH SYNOPSIS
@@ -109,7 +109,7 @@ Report bugs to zutils\-bug@nongnu.org
 .br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2017 Antonio Diaz Diaz.
+Copyright \(co 2018 Antonio Diaz Diaz.
 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
 .br
 This is free software: you are free to change and redistribute it.

doc/zgrep.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.46.1.
-.TH ZGREP "1" "April 2017" "zgrep (zutils) 1.6" "User Commands"
+.TH ZGREP "1" "February 2018" "zgrep (zutils) 1.7" "User Commands"
 .SH NAME
 zgrep \- search compressed files for a regular expression
 .SH SYNOPSIS
@@ -47,6 +47,9 @@ only print a count of matching lines per file
 \fB\-C\fR, \fB\-\-context=\fR<n>
 print <n> lines of output context
 .TP
+\fB\-\-color[=\fR<when>]
+show matched strings in color
+.TP
 \fB\-e\fR, \fB\-\-regexp=\fR<pattern>
 use <pattern> as the pattern to match
 .TP
@@ -135,7 +138,7 @@ Report bugs to zutils\-bug@nongnu.org
 .br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2017 Antonio Diaz Diaz.
+Copyright \(co 2018 Antonio Diaz Diaz.
 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
 .br
 This is free software: you are free to change and redistribute it.

doc/ztest.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.46.1.
-.TH ZTEST "1" "April 2017" "ztest (zutils) 1.6" "User Commands"
+.TH ZTEST "1" "February 2018" "ztest (zutils) 1.7" "User Commands"
 .SH NAME
 ztest \- verify the integrity of compressed files
 .SH SYNOPSIS
@@ -66,7 +66,7 @@ Report bugs to zutils\-bug@nongnu.org
 .br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2017 Antonio Diaz Diaz.
+Copyright \(co 2018 Antonio Diaz Diaz.
 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
 .br
 This is free software: you are free to change and redistribute it.

doc/zupdate.1

@@ -1,5 +1,5 @@
 .\" DO NOT MODIFY THIS FILE!  It was generated by help2man 1.46.1.
-.TH ZUPDATE "1" "April 2017" "zupdate (zutils) 1.6" "User Commands"
+.TH ZUPDATE "1" "February 2018" "zupdate (zutils) 1.7" "User Commands"
 .SH NAME
 zupdate \- recompress bzip2, gzip, xz files to lzip format
 .SH SYNOPSIS
@@ -76,7 +76,7 @@ Report bugs to zutils\-bug@nongnu.org
 .br
 Zutils home page: http://www.nongnu.org/zutils/zutils.html
 .SH COPYRIGHT
-Copyright \(co 2017 Antonio Diaz Diaz.
+Copyright \(co 2018 Antonio Diaz Diaz.
 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
 .br
 This is free software: you are free to change and redistribute it.

doc/zutils.info

@@ -12,7 +12,7 @@ File: zutils.info,  Node: Top,  Next: Introduction,  Up: (dir)
 Zutils Manual
 *************
 
-This manual is for Zutils (version 1.6, 5 April 2017).
+This manual is for Zutils (version 1.7, 13 February 2018).
 
 * Menu:
 
@@ -29,7 +29,7 @@ This manual is for Zutils (version 1.6, 5 April 2017).
 * Concept index::       Index of concepts
 
 
-   Copyright (C) 2009-2017 Antonio Diaz Diaz.
+   Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
    This manual is free documentation: you have unlimited permission to
 copy, distribute and modify it.
@@ -40,7 +40,7 @@ File: zutils.info,  Node: Introduction,  Next: Common options,  Prev: Top,  Up:
 1 Introduction
 **************
 
-Zutils is a collection of utilities able to deal with any combination of
+Zutils is a collection of utilities able to process any combination of
 compressed and uncompressed files transparently. If any given file,
 including standard input, is compressed, its decompressed content is
 used. Compressed files are decompressed on the fly; no temporary files
@@ -372,7 +372,8 @@ following:
 An exit status of 0 means no differences were found, 1 means some
 differences were found, and 2 means trouble.
 
-   zdiff supports the following options:
+   zdiff supports the following options (some options only work if the
+diff program used supports them):
 
 '-a'
 '--text'
@@ -472,7 +473,8 @@ or all in the same compression format.
 An exit status of 0 means at least one match was found, 1 means no
 matches were found, and 2 means trouble.
 
-   zgrep supports the following options:
+   zgrep supports the following options (some options only work if the
+grep program used supports them):
 
 '-a'
 '--text'
@@ -498,6 +500,9 @@ matches were found, and 2 means trouble.
 '--context=N'
      Print N lines of output context.
 
+'--color[=WHEN]'
+     Show matched strings in color. WHEN is 'never', 'always' or 'auto'.
+
 '-e PATTERN'
 '--regexp=PATTERN'
      Use PATTERN as the pattern to match.
@@ -765,18 +770,18 @@ Concept index
 
 Tag Table:
 Node: Top222
-Node: Introduction1147
+Node: Introduction1151
-Node: Common options3773
+Node: Common options3775
-Ref: compressor-requirements5531
+Ref: compressor-requirements5533
-Node: The zutilsrc file5903
+Node: The zutilsrc file5905
-Node: Zcat6828
+Node: Zcat6830
-Node: Zcmp8882
+Node: Zcmp8884
-Node: Zdiff11341
+Node: Zdiff11343
-Node: Zgrep13981
+Node: Zgrep14047
-Node: Ztest17320
+Node: Ztest17541
-Node: Zupdate19154
+Node: Zupdate19375
-Node: Problems22026
+Node: Problems22247
-Node: Concept index22560
+Node: Concept index22781
 
 End Tag Table
 

doc/zutils.texi

@@ -6,8 +6,8 @@
 @finalout
 @c %**end of header
 
-@set UPDATED 5 April 2017
+@set UPDATED 13 February 2018
-@set VERSION 1.6
+@set VERSION 1.7
 
 @dircategory Data Compression
 @direntry
@@ -49,7 +49,7 @@ This manual is for Zutils (version @value{VERSION}, @value{UPDATED}).
 @end menu
 
 @sp 1
-Copyright @copyright{} 2009-2017 Antonio Diaz Diaz.
+Copyright @copyright{} 2009-2018 Antonio Diaz Diaz.
 
 This manual is free documentation: you have unlimited permission
 to copy, distribute and modify it.
@@ -59,7 +59,7 @@ to copy, distribute and modify it.
 @chapter Introduction
 @cindex introduction
 
-Zutils is a collection of utilities able to deal with any combination of
+Zutils is a collection of utilities able to process any combination of
 compressed and uncompressed files transparently. If any given file,
 including standard input, is compressed, its decompressed content is
 used. Compressed files are decompressed on the fly; no temporary files
@@ -421,7 +421,8 @@ standard input.
 An exit status of 0 means no differences were found, 1 means some
 differences were found, and 2 means trouble.
 
-zdiff supports the following options:
+zdiff supports the following options (some options only work if the diff
+program used supports them):
 
 @table @code
 @item -a
@@ -525,7 +526,8 @@ zgrep [@var{options}] @var{pattern} [@var{files}]
 An exit status of 0 means at least one match was found, 1 means no
 matches were found, and 2 means trouble.
 
-zgrep supports the following options:
+zgrep supports the following options (some options only work if the grep
+program used supports them):
 
 @table @code
 @item -a
@@ -552,6 +554,10 @@ Only print a count of matching lines per file.
 @itemx --context=@var{n}
 Print @var{n} lines of output context.
 
+@item --color[=@var{when}]
+Show matched strings in color. @var{when} is @samp{never}, @samp{always}
+or @samp{auto}.
+
 @item -e @var{pattern}
 @itemx --regexp=@var{pattern}
 Use @var{pattern} as the pattern to match.

rc.cc

@@ -1,5 +1,5 @@
 /*  Zutils - Utilities dealing with compressed files
-    Copyright (C) 2009-2017 Antonio Diaz Diaz.
+    Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -37,7 +37,7 @@ int verbosity = 0;
 namespace {
 
 const char * const config_file_name = "zutilsrc";
-const char * const     program_year = "2017";
+const char * const     program_year = "2018";
 
 std::string compressor_names[num_formats] =
   { "bzip2", "gzip", "lzip", "xz" };		// default compressor names

rc.h

@@ -1,5 +1,5 @@
 /*  Zutils - Utilities dealing with compressed files
-    Copyright (C) 2009-2017 Antonio Diaz Diaz.
+    Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

recursive.cc

@@ -1,5 +1,5 @@
 /*  Zutils - Utilities dealing with compressed files
-    Copyright (C) 2009-2017 Antonio Diaz Diaz.
+    Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

testsuite/check.sh

@@ -1,6 +1,6 @@
 #! /bin/sh
 # check script for Zutils - Utilities dealing with compressed files
-# Copyright (C) 2009-2017 Antonio Diaz Diaz.
+# Copyright (C) 2009-2018 Antonio Diaz Diaz.
 #
 # This script is free software: you have unlimited permission
 # to copy, distribute and modify it.
@@ -41,6 +41,8 @@ cd "${objdir}"/tmp || framework_failure
 for i in ${compressors}; do
 	cat "${testdir}"/test.txt > in || framework_failure
 	$i in || compressor_needed
+	printf "Hello World!\n" > hello || framework_failure
+	$i hello || compressor_needed
 done
 
 cat "${testdir}"/test.txt > in || framework_failure
@@ -234,6 +236,10 @@ printf "\ntesting   zgrep-%s..." "$2"
 
 for i in ${extensions}; do
 	"${ZGREP}" -N "GNU" in.$i > /dev/null || test_failed $LINENO $i
+	"${ZGREP}" -N "GNU" in.$i hello.$i > /dev/null || test_failed $LINENO $i
+	"${ZGREP}" -N "GNU" hello.$i in.$i > /dev/null || test_failed $LINENO $i
+	"${ZGREP}" -N -q "GNU" in.$i hello.$i || test_failed $LINENO $i
+	"${ZGREP}" -N -q "GNU" hello.$i in.$i || test_failed $LINENO $i
 	"${ZGREP}" -N "GNU" < in.$i > /dev/null || test_failed $LINENO $i
 	"${ZGREP}" -N -l "GNU" in.$i > /dev/null || test_failed $LINENO $i
 	"${ZGREP}" -N -L "GNU" in.$i || test_failed $LINENO $i

zcat.cc

@@ -1,5 +1,5 @@
 /*  Zcat - decompress and concatenate files to standard output
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zcatgrep.cc

@@ -1,5 +1,5 @@
 /*  Common code for zcat and zgrep
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zcmp.cc

@@ -1,5 +1,5 @@
 /*  Zcmp - decompress and compare two files byte by byte
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zcmpdiff.cc

@@ -1,5 +1,5 @@
 /*  Common code for zcmp and zdiff
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zdiff.cc

@@ -1,5 +1,5 @@
 /*  Zdiff - decompress and compare two files line by line
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zgrep.cc

@@ -1,5 +1,5 @@
 /*  Zgrep - search compressed files for a regular expression
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -69,6 +69,7 @@ void show_help()
                "  -B, --before-context=<n>   print <n> lines of leading context\n"
                "  -c, --count                only print a count of matching lines per file\n"
                "  -C, --context=<n>          print <n> lines of output context\n"
+               "      --color[=<when>]       show matched strings in color\n"
                "  -e, --regexp=<pattern>     use <pattern> as the pattern to match\n"
                "  -E, --extended-regexp      <pattern> is an extended regular expression\n"
                "  -f, --file=<file>          obtain patterns from <file>\n"
@@ -209,7 +210,8 @@ int zgrep_file( int infd, const int format_index,
 
 int main( const int argc, const char * const argv[] )
   {
-  enum { help_opt = 256, verbose_opt, bz2_opt, gz_opt, lz_opt, xz_opt };
+  enum { help_opt = 256, verbose_opt, color_opt,
+         bz2_opt, gz_opt, lz_opt, xz_opt };
   int format_index = -1;
   int infd = -1;
   int list_mode = 0;		// 1 = list matches, -1 = list non matches
@@ -219,6 +221,7 @@ int main( const int argc, const char * const argv[] )
   std::string input_filename;
   std::list< std::string > filenames;
   std::vector< const char * > grep_args;	// args to grep, maybe empty
+  std::string color_option;		// needed because of optional arg
   invocation_name = argv[0];
   program_name = "zgrep";
 
@@ -255,6 +258,7 @@ int main( const int argc, const char * const argv[] )
     { 'x', "line-regexp",         Arg_parser::no  },	// grep
     { help_opt,    "help",        Arg_parser::no  },
     { verbose_opt, "verbose",     Arg_parser::no  },
+    { color_opt,   "color",       Arg_parser::maybe },
     { bz2_opt,     "bz2",         Arg_parser::yes },
     { gz_opt,      "gz",          Arg_parser::yes },
     { lz_opt,      "lz",          Arg_parser::yes },
@@ -314,6 +318,9 @@ int main( const int argc, const char * const argv[] )
       case help_opt   : show_help(); return 0;
       case verbose_opt: if( verbosity < 4 ) ++verbosity;
                         no_messages = false; break;
+      case color_opt: color_option = "--color";
+        if( !arg.empty() ) { color_option += '='; color_option += arg; }
+        break;
       case bz2_opt: parse_compressor( arg, fmt_bz2 ); break;
       case gz_opt: parse_compressor( arg, fmt_gz ); break;
       case lz_opt: parse_compressor( arg, fmt_lz ); break;
@@ -322,6 +329,9 @@ int main( const int argc, const char * const argv[] )
       }
     } // end process options
 
+  if( !color_option.empty() )		// push the last value set
+    grep_args.push_back( color_option.c_str() );
+
 #if defined(__MSVCRT__) || defined(__OS2__)
   setmode( STDIN_FILENO, O_BINARY );
   setmode( STDOUT_FILENO, O_BINARY );

ztest.cc

@@ -1,5 +1,5 @@
 /*  Ztest - verify the integrity of compressed files
-    Copyright (C) 2010-2017 Antonio Diaz Diaz.
+    Copyright (C) 2010-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zupdate.cc

@@ -1,5 +1,5 @@
 /*  Zupdate - recompress bzip2, gzip, xz files to lzip format
-    Copyright (C) 2013-2017 Antonio Diaz Diaz.
+    Copyright (C) 2013-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zutils.cc

@@ -1,5 +1,5 @@
 /*  Zutils - Utilities dealing with compressed files
-    Copyright (C) 2009-2017 Antonio Diaz Diaz.
+    Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by

zutils.h

@@ -1,5 +1,5 @@
 /*  Zutils - Utilities dealing with compressed files
-    Copyright (C) 2009-2017 Antonio Diaz Diaz.
+    Copyright (C) 2009-2018 Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by