table of contents
Term::Cap(3pm) | Perl Programmers Reference Guide | Term::Cap(3pm) |
NAME¶
Term::Cap - Perl termcap interface
SYNOPSIS¶
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);
DESCRIPTION¶
These are low-level functions to extract and use capabilities from a terminal capability (termcap) database.
More information on the terminal capabilities will be found in the termcap manpage on most Unix-like systems.
METHODS¶
print $terminal->Tpad($self->{_xx}, 1);
Tgoto, Tputs, and Tpad return the string and will also output the string to $FH if specified.
Tgetent
Returns a blessed object reference which the user can then use to send the control strings to the terminal using Tputs and Tgoto.
The 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 $HOME/.termcap, /etc/termcap, and /usr/share/misc/termcap, in that order, unless the environment variable TERMPATH exists, in which case it specifies a list of file pathnames (separated by spaces or colons) to be searched instead. Whenever multiple files are searched and a tc field occurs in the requested entry, the entry it names must be found in the same file or one of the succeeding files. If there is a ":tc=...:" in the TERMCAP environment variable string it will continue the search in the files as above.
The extracted termcap entry is available in the object as "$self->{TERMCAP}".
It takes a hash reference as an argument with two optional keys:
- OSPEED
- The terminal output bit rate (often mistakenly called the baud rate) for this terminal - if not set a warning will be generated and it will be defaulted to 9600. OSPEED can be be specified as either a POSIX termios/SYSV termio speeds (where 9600 equals 9600) or an old DSD-style speed ( where 13 equals 9600).
- TERM
- The terminal type whose termcap entry will be used - if not supplied it will default to $ENV{TERM}: if that is not set then Tgetent will croak.
It calls "croak" on failure.
Tpad
Outputs a literal string with appropriate padding for the current terminal.
It takes three arguments:
- $string
- The literal string to be output. If it starts with a number and an optional '*' then the padding will be increased by an amount relative to this number, if the '*' is present then this amount will me multiplied by $cnt. This part of $string is removed before output/
- $cnt
- Will be used to modify the padding applied to string as described above.
- $FH
- An optional filehandle (or IO::Handle ) that output will be printed to.
The padded $string is returned.
Tputs
Output the string for the given capability padded as appropriate without any parameter substitution.
It takes three arguments:
- $cap
- The capability whose string is to be output.
- $cnt
- A count passed to Tpad to modify the padding applied to the output string. If $cnt is zero or one then the resulting string will be cached.
- $FH
- An optional filehandle (or IO::Handle ) that output will be printed to.
The appropriate string for the capability will be returned.
Tgoto
Tgoto decodes a cursor addressing string with the given parameters.
There are four arguments:
- $cap
- The name of the capability to be output.
- $col
- The first value to be substituted in the output string ( usually the column in a cursor addressing capability )
- $row
- The second value to be substituted in the output string (usually the row in cursor addressing capabilities)
- $FH
- An optional filehandle (or IO::Handle ) to which the output string will be printed.
Substitutions are made with $col and $row in the output string with the following sprintf() line formats:
%% output `%' %d output value as in printf %d %2 output value as in printf %2d %3 output value as in printf %3d %. output value as in printf %c %+x add x to value, then do %. %>xy if value > x then add y, no output %r reverse order of two parameters, no output %i increment by one, no output %B BCD (16*(value/10)) + (value%10), no output %n exclusive-or all parameters with 0140 (Datamedia 2500) %D Reverse coding (value - 2*(value%16)), no output (Delta Data)
The output string will be returned.
Trequire
Takes a list of capabilities as an argument and will croak if one is not found.
EXAMPLES¶
use Term::Cap; # Get terminal output speed require POSIX; my $termios = new POSIX::Termios; $termios->getattr; my $ospeed = $termios->getospeed; # Old-style ioctl code to get ospeed: # require 'ioctl.pl'; # ioctl(TTY,$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);
COPYRIGHT AND LICENSE¶
Please see the README file in distribution.
AUTHOR¶
This module is part of the core Perl distribution and is also maintained for CPAN by Jonathan Stowe <jns@gellyfish.com>.
SEE ALSO¶
POD ERRORS¶
Hey! The above document had some coding errors, which are explained below:
- Around line 89:
- You can't have =items (as at line 148) unless the first thing after the =over is an =item
2009-02-12 | perl v5.10.1 |