"David Storrs" <[EMAIL PROTECTED]> wrote > # Print file, inefficiently > print $default.readline for 1..$default.lines;
print it efficiently: print $default; > # Append a line > $rw .= "an additional line\n"; $rw ~= "\n" unless $rw.chars[-1] eq "\n"; $rw ~= "an additional line\n"; > # New line is visible through $rw > print $rw.lines[-1]; # (*) > > # last line not yet visible through $default because it was > # added by external handle--just like in a tail -f, we > # need to move file pointer manually > $default.seek(File.current_pos); I don't think the manual sync is really needed: name the method something a bit more neutral: $default.refresh; > (*) The .lines[-1] semantic is feasible if we are willing to tolerate > very slow performance (at least the first time; it could cache the > locations of $/ after scanning and dump the cache if $/ changes), the > fact that it wouldn't work on all files (/dev/null, /dev/zero, etc), > and a few other issues. The performance here could depend on the encoding. If the file is ASCII, then we don't need to worry about multi-byte characters, so the under-the-hood implementation could follow a heuristic such as "seek to 1000 bytes from end of file: scan forward for "\n". If none found, then go back further. Otherwise continue to scan to find last "\n" in the file". Dave.
