comm: adapt GNU error messages

util/gnu-patches/tests_comm.pl.patch

@@ -0,0 +1,44 @@
+diff --git a/tests/misc/comm.pl b/tests/misc/comm.pl
+index 5bd5f56d7..8322d92ba 100755
+--- a/tests/misc/comm.pl
++++ b/tests/misc/comm.pl
+@@ -73,18 +73,24 @@ my @Tests =
+
+    # invalid missing command line argument (1)
+    ['missing-arg1', $inputs[0], {EXIT=>1},
+-    {ERR => "$prog: missing operand after 'a'\n"
+-        . "Try '$prog --help' for more information.\n"}],
++    {ERR => "error: the following required arguments were not provided:\n"
++        . "  <FILE2>\n\n"
++        . "Usage: $prog [OPTION]... FILE1 FILE2\n\n"
++        . "For more information, try '--help'.\n"}],
+
+    # invalid missing command line argument (both)
+    ['missing-arg2', {EXIT=>1},
+-    {ERR => "$prog: missing operand\n"
+-        . "Try '$prog --help' for more information.\n"}],
++    {ERR => "error: the following required arguments were not provided:\n"
++        . "  <FILE1>\n"
++        . "  <FILE2>\n\n"
++        . "Usage: $prog [OPTION]... FILE1 FILE2\n\n"
++        . "For more information, try '--help'.\n"}],
+
+    # invalid extra command line argument
+    ['extra-arg', @inputs, 'no-such', {EXIT=>1},
+-    {ERR => "$prog: extra operand 'no-such'\n"
+-        . "Try '$prog --help' for more information.\n"}],
++    {ERR => "error: unexpected argument 'no-such' found\n\n"
++        . "Usage: $prog [OPTION]... FILE1 FILE2\n\n"
++        . "For more information, try '--help'.\n"}],
+
+    # out-of-order input
+    ['ooo', {IN=>{a=>"1\n3"}}, {IN=>{b=>"3\n2"}}, {EXIT=>1},
+@@ -163,7 +169,7 @@ my @Tests =
+
+    # invalid dual delimiter
+    ['delim-dual', '--output-delimiter=,', '--output-delimiter=+', @inputs,
+-    {EXIT=>1}, {ERR => "$prog: multiple output delimiters specified\n"}],
++    {EXIT=>1}, {ERR => "$prog: multiple conflicting output delimiters specified\n"}],
+
+    # valid dual delimiter specification
+    ['delim-dual2', '--output-delimiter=,', '--output-delimiter=,', @inputs,