bug#47535: 27.2; comint shell hangs on long input

classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

bug#47535: 27.2; comint shell hangs on long input

Emacs - Bugs mailing list
Start Emacs with emacs -Q

M-x shell

in the shell buffer, enter

echo <C-u> 1 0 0 0 x <Return>

to echo 1,000 x's. Works fine.

echo <C-u> 1 0 2 4 x <Return>

to echo 1,024 x's. The shell buffer prints the command, then "hangs" and
the output is never printed, and the command prompt not issued. no
character input works (Return, etc.)

A ^G character does show up for some reason, although I did not press Ctrl-G.
If

You must use C-c C-c comint-interrupt-subjob to get back to the shell prompt.

In GNU Emacs 27.2 (build 1, x86_64-apple-darwin18.7.0, NS appkit-1671.60 Version 10.14.6 (Build 18G95))
 of 2021-03-27 built on builder10-14.porkrind.org
Windowing system distributor 'Apple', version 10.3.1894
System Description:  Mac OS X 10.15.7

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

Configured using:
 'configure --with-ns '--enable-locallisppath=/Library/Application
 Support/Emacs/${version}/site-lisp:/Library/Application
 Support/Emacs/site-lisp' --with-modules'

Configured features:
NOTIFY KQUEUE ACL GNUTLS LIBXML2 ZLIB TOOLKIT_SCROLL_BARS NS MODULES
THREADS JSON PDUMPER GMP

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Fundamental

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs
format-spec rfc822 mml easymenu mml-sec password-cache epa derived epg
epg-config gnus-util rmail rmail-loaddefs text-property-search seq
byte-opt gv bytecomp byte-compile cconv mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils time-date subr-x
cl-loaddefs cl-lib tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel term/ns-win ns-win ucs-normalize mule-util
term/common-win tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite charscript charprop case-table epa-hook
jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice loaddefs
button faces cus-face macroexp files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote threads kqueue cocoa ns multi-tty make-network-process emacs)

Memory information:
((conses 16 45079 7412)
 (symbols 48 5929 1)
 (strings 32 15297 2156)
 (string-bytes 1 507876)
 (vectors 16 10216)
 (vector-slots 8 127221 7646)
 (floats 8 19 52)
 (intervals 56 190 0)
 (buffers 1000 13))


Disclaimer: The information in this message may be proprietary and/or confidential, and protected from disclosure. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify Apiture immediately by replying to this message and deleting it from your computer.
Reply | Threaded
Open this post in threaded view
|

bug#47535: 27.2; comint shell hangs on long input

Andreas Schwab-2
On Mär 31 2021, David Biesack via "Bug reports for GNU Emacs, the Swiss army knife of text editors" wrote:

> Start Emacs with emacs -Q
>
> M-x shell
>
> in the shell buffer, enter
>
> echo <C-u> 1 0 0 0 x <Return>
>
> to echo 1,000 x's. Works fine.
>
> echo <C-u> 1 0 2 4 x <Return>
>
> to echo 1,024 x's. The shell buffer prints the command, then "hangs" and
> the output is never printed, and the command prompt not issued. no
> character input works (Return, etc.)

That's a limitation of the BSD tty interface.  Once the input buffer is
full, no more characters can be sent, not even a newline or the EOF
character.  The Linux tty interface instead discards further input until
the newline or EOF.

Andreas.

--
Andreas Schwab, [hidden email]
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."