prefer SIGINFO for statistics if available

[barcat.git] / barcat

diff --git a/barcat b/barcat
index 1818493a8af4603898a2e4b7f1265c6bcfda948d..de3f6f8459721ae78c734401961607eaef4c4e20 100755 (executable)
--- a/barcat
+++ b/barcat
@@ -43,6 +43,9 @@ GetOptions(\%opt,
                );
        },
        'markers|m=s',
+       'graph-format=s' => sub {
+               $opt{'graph-format'} = substr $_[1], 0, 1;
+       },
        'spark:s' => sub {
                $opt{spark} = [split //, $_[1] || '⎽▁▂▃▄▅▆▇█'];
        },
@@ -75,6 +78,7 @@ GetOptions(\%opt,
 
 $opt{width} ||= $ENV{COLUMNS} || 80;
 $opt{color} //= -t *STDOUT;  # enable on tty
+$opt{'graph-format'} //= '-';
 $opt{trim}   *= $opt{width} / 100 if $opt{trimpct};
 $opt{units}   = [split //, ' kMGTPEZYyzafpnμm'] if $opt{'human-readable'};
 $opt{anchor} //= qr/\A/;
@@ -83,13 +87,15 @@ $opt{'value-length'} = 1 if $opt{unmodified};
 
 my (@lines, @values, @order);
 
+$SIG{$_} = \&show_stat for exists $SIG{INFO} ? 'INFO' : 'QUIT';
+$SIG{ALRM} = sub {
+       show_lines();
+       alarm $opt{interval} if defined $opt{interval} and $opt{interval} > 0;
+};
+
 if (defined $opt{interval}) {
        $opt{interval} ||= 1;
-       $SIG{ALRM} = sub {
-               show_lines();
-               alarm $opt{interval};
-       };
-       alarm $opt{interval};
+       alarm $opt{interval} if $opt{interval} > 0;
 
        eval {
                require Tie::Array::Sorted;
@@ -99,6 +105,7 @@ if (defined $opt{interval}) {
 
 $SIG{INT} = sub {
        $SIG{INT} = 'DEFAULT';  # reset for subsequent attempts
+       exit if !$.;
        'IGNORE' # continue after assumed eof
 };
 
@@ -119,6 +126,8 @@ while (readline) {
                }
        }
        push @lines, $_;
+       show_lines() if defined $opt{interval} and $opt{interval} < 0
+               and $. % $opt{interval} == 0;
 }
 
 $SIG{INT} = 'DEFAULT';
@@ -201,7 +210,7 @@ while ($nr <= $#lines) {
        }
        my $line = $lines[$nr] =~ s/\n/$val/r;
        printf '%-*s', $len + length($val), $line;
-       print $barmark[$_] // '-' for 1 .. $size && (($values[$nr] || 0) - $minval) * $size + .5;
+       print $barmark[$_] // $opt{'graph-format'} for 1 .. $size && (($values[$nr] || 0) - $minval) * $size + .5;
        say '';
 }
 continue {
@@ -212,7 +221,7 @@ say '' if $opt{spark};
 }
 show_lines();
 
-if ($opt{stat}) {
+sub show_stat {
        if ($opt{hidemin} or $opt{hidemax}) {
                $opt{hidemin} ||= 1;
                $opt{hidemax} ||= @lines;
@@ -230,6 +239,7 @@ if ($opt{stat}) {
        }
        say '';
 }
+show_stat() if $opt{stat};
 
 __END__
 =encoding utf8
@@ -283,9 +293,10 @@ turning long numbers like I<12356789> into I<12.4M>.
 Also changes an exponent I<1.602176634e-19> to I<160.2z>.
 Short integers are aligned but kept without decimal point.
 
-=item -t, --interval[=<seconds>]
+=item -t, --interval[=(<seconds>|-<lines>)]
 
-Interval time to output partial progress.
+Output partial progress every given number of seconds or input lines.
+An update can also be forced by sending a I<SIGALRM> alarm signal.
 
 =item -l, --length=[-]<size>[%]
 
@@ -303,6 +314,11 @@ Stop output after a number of lines.
 All input is still counted and analyzed for statistics,
 but disregarded for padding and bar size.
 
+=item --graph-format=<character>
+
+Glyph to repeat for the graph line.
+Defaults to a dash C<->.
+
 =item -m, --markers=
 
 Statistical positions to indicate on bars.