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Full Discussion: Bash replacement to getchar
Top Forums Shell Programming and Scripting Bash replacement to getchar Post 302343881 by kshji on Friday 14th of August 2009 02:23:34 AM
Old 08-14-2009
With this you can debug:
Code:
trap 'echo "int shell"' HUP INT QUIT
echo -n "Press key:"
stty -echo raw
c=$(dd bs=1 count=1 2>/dev/null )
stty echo -raw
echo "<$c>"
echo $c | od -c

echo "press ctrl-c"
sleep 20

result: dd read one char from stdin. Also ctrl-c and ctrl-d are only chars. So you can test those chars.

Code:
trap ':'  HUP INT QUIT
c=""
while [ "$c" = "" ]
do
  # do c read, look previous dd or
  echo -n "key:"
  read -n 1 c 
  # test it
  case "$c" in
    \001) ;; # ctrl-A
    \003) ;; # ctrl-C
  esac
  # remove char ascii 01-04
  c=$(echo "$c" | tr -d "[\001-\004]" )
done

 

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LEARN ABOUT SUSE

ansi_ctrlu

term::ansi::ctrl::unix(n)					 Terminal control					 term::ansi::ctrl::unix(n)

__________________________________________________________________________________________________________________________________________________

NAME

       term::ansi::ctrl::unix - Control operations and queries

SYNOPSIS

       package require Tcl  8.4

       package require term::ansi::ctrl::unix  ?0.1?

       ::term::ansi::ctrl::unix::import ?ns? ?arg...?

       ::term::ansi::ctrl::unix::raw

       ::term::ansi::ctrl::unix::raw

       ::term::ansi::ctrl::unix::columns

       ::term::ansi::ctrl::unix::rows

_________________________________________________________________

DESCRIPTION

       WARNING:  This  package	is  unix-specific  and depends on the availability of two unix system commands for terminal control, i.e. stty and
       tput, both of which have to be found in the $PATH. If any of these two commands is missing the loading of the package will fail.

       The package provides commands to switch the standard input of the current process between raw and cooked input modes, and to query the size
       of terminals, i.e. the available number of columns and lines.

API

   INTROSPECTION
       ::term::ansi::ctrl::unix::import ?ns? ?arg...?
	      This  command imports some or all attribute commands into the namespace ns. This is by default the namespace ctrl. Note that this is
	      relative namespace name, placing the imported command into a child of the current namespace. By default all commands  are  imported,
	      this can howver be restricted by listing the names of the wanted commands after the namespace argument.

   OPERATIONS
       ::term::ansi::ctrl::unix::raw
	      This command switches the standard input of the current process to raw input mode. This means that from then on all characters typed
	      by the user are immediately reported to the application instead of waiting in the OS buffer until the Enter/Return key is received.

       ::term::ansi::ctrl::unix::raw
	      This command switches the standard input of the current process to cooked input mode. This means that from then  on  all	characters
	      typed by the user are kept in OS buffers for editing until the Enter/Return key is received.

       ::term::ansi::ctrl::unix::columns
	      This command queries the terminal connected to the standard input for the number of columns available for display.

       ::term::ansi::ctrl::unix::rows
	      This command queries the terminal connected to the standard input for the number of rows (aka lines) available for display.

BUGS, IDEAS, FEEDBACK
       This  document, and the package it describes, will undoubtedly contain bugs and other problems.	Please report such in the category term of
       the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883].  Please also report any ideas for enhancements you  may  have  for
       either package and/or documentation.

KEYWORDS

       ansi, columns, control, cooked, input mode, lines, raw, rows, terminal

COPYRIGHT

       Copyright (c) 2006 Andreas Kupries <andreas_kupries@users.sourceforge.net>

term									0.1						 term::ansi::ctrl::unix(n)
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