• tty_fd is now never closed
• new tty_hasstate tracks tty_state (cf. thread around
http://article.gmane.org/gmane.os.miros.mksh/79 and PLD bug)
• as users requested, importing COLUMNS or LINES from the environment
now removes its special-ness as does unsetting it
• otherwise, setting COLUMNS or LINES is honoured until the next SIGWINCH
arrives or change_winsz is otherwise run (e.g. before displaying the
prompt in the interactive command line editing modes)
• SIGWINCH is now honoured before each reading of $COLUMNS and $LINES too
• change the Uhr to match – it no longer calls stty(1) ☺
• all writers of exstat ensure the value is in [0; 0xFF]
• all readers of exstat AND it with 0xFF (not strictly needed thus)
• trap_exstat is “safe”, i.e. always either -1 or [0; 0xFF]
several conditions are met as outlined below; for more background, refer to
http://www.FreeBSD.org/cgi/query-pr.cgi?pr=113860
We don’t yet optimise 「% sh -c '{ echo a; sleep 10;}&'; sleep 1; ps T」 so
the FreeBSD® sh approach cannot work for us, but scanning the “sh -c” argu‐
ment for disallowed characters and, if not, setting a flag that enables the
shell to exec the tree when parsed as TCOM *and not c_trap()* was possible.
Disallowed characters are currently C_QUOTE except space, that is:
Tab Newline " # $ & ' ( ) * ; < = > ? [ \ ] ` |
This should catch all cases of magic, variables, subshells, pipelines, etc.
XXX we could track whether tty_fd has already been successfully opened,
XXX the ttystate initialised, and then just never close it unless it is
XXX necessary, then we can keep COLUMNS/LINES accurate in scripts, even
is not found, from a suggestion by RT (LP: #912691)
• try harder (in a loop) to acquire a file lock if the locking mechanism
documents EINTR is a possibility (fcntl always, flock on Linux not .Ox)
• use -std=c99 not -std=gnu99 if it must be at all
if we find any, but not later; do not check on every read
⇒ allows changing COLUMNS and LINES (independent of each other, or both)
for script shells by passing them in an environment setting, even if
we get a tty; interactive shells still check before each line is read…
reported by the PLD guys, thanks
tg