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Term::Cap - Perl termcap interface


require Term::Cap;
$terminal = Tgetent Term::Cap { TERM => undef, OSPEED => $ospeed };
$terminal->Trequire(qw/ce ku kd/);
$terminal->Tgoto('cm', $col, $row, $FH);
$terminal->Tputs('dl', $count, $FH);
$terminal->Tpad($string, $count, $FH);


These are low-level functions to extract and use capabilities from a terminal capability (termcap) database.

The Tgetent function extracts the entry of the specified terminal type TERM (defaults to the environment variable TERM) from the database.

It will look in the environment for a TERMCAP variable. If found, and the value does not begin with a slash, and the terminal type name is the same as the environment string TERM, the TERMCAP string is used instead of reading a termcap file. If it does begin with a slash, the string is used as a path name of the termcap file to search. If TERMCAP does not begin with a slash and name is different from TERM, Tgetent searches the files $HOME/.termcap, /etc/termcap, and /usr/share/misc/termcap, in that order, unless the environment variable TERMPATH exists, in which case it specifies a list of file pathnames (separated by spaces or colons) to be searched instead. Whenever multiple files are searched and a tc field occurs in the requested entry, the entry it names must be found in the same file or one of the succeeding files. If there is a :tc=...: in the TERMCAP environment variable string it will continue the search in the files as above.

OSPEED is the terminal output bit rate (often mistakenly called the baud rate). OSPEED can be specified as either a POSIX termios/SYSV termio speeds (where 9600 equals 9600) or an old BSD-style speeds (where 13 equals 9600).

Tgetent returns a blessed object reference which the user can then use to send the control strings to the terminal using Tputs and Tgoto. It calls croak on failure.

Tgoto decodes a cursor addressing string with the given parameters.

The output strings for Tputs are cached for counts of 1 for performance. Tgoto and Tpad do not cache. $self->{_xx} is the raw termcap data and $self->{xx} is the cached version.

print $terminal->Tpad($self->{_xx}, 1);

Tgoto, Tputs, and Tpad return the string and will also output the string to $FH if specified.

The extracted termcap entry is available in the object as $self->{TERMCAP}.


# Get terminal output speed
require POSIX;
my $termios = new POSIX::Termios;
my $ospeed = $termios->getospeed;

# Old-style ioctl code to get ospeed:
#     require '';
#     ioctl(TTY,$TIOCGETP,$sgtty);
#     ($ispeed,$ospeed) = unpack('cc',$sgtty);

# allocate and initialize a terminal structure
$terminal = Tgetent Term::Cap { TERM => undef, OSPEED => $ospeed };

# require certain capabilities to be available
$terminal->Trequire(qw/ce ku kd/);

# Output Routines, if $FH is undefined these just return the string

# Tgoto does the % expansion stuff with the given args
$terminal->Tgoto('cm', $col, $row, $FH);

# Tputs doesn't do any % expansion.
$terminal->Tputs('dl', $count = 1, $FH);