Exercises, examples and other material relating to training module P305. This module is presented on Private Courses and Specially Run Courses only

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Giving up on user input - keyboard timeout in Perl There's an old piece of code that I've used to demontstrate how (in Perl) you can prompt for a user input ... but then time out the input on an alarm ... http://www.wellho.net/mouth/2382_Giv ... -Perl.html  [short article]

Keyboard reading in Perl - character by character not line by line If I'm typing in my age in response to a prompt and I start with a "6" character, will you assume that I'm between 60 and 69 years old? You might ... ... http://www.wellho.net/mouth/2213_Key ... -line.html  [short article]

Different perl examples - some corners I rarely explore The private Perl course that I ran on Wednesday through Friday of last week was a little out of the ordinary as we were concentrating far more that usual ... http://www.wellho.net/mouth/2876_Dif ... plore.html  [short article]

print out ASCII decimal equivalents of entries #!/usr/bin/perl # keyboard input while (1) { print "Please enter information: " if (-t STDIN); $abc = ; @chars = unpack("C" x ... http://www.wellho.net/resources/ex.php4?item=p305/keyin  [code sample]

Binary file copy #!/usr/bin/perl # copy a file $in = "postcodes"; $out = "pc.bak"; open (IN,$in); open (OUT,">$out"); print OUT $buffer while (read (IN,$buffer,65536)); http://www.wellho.net/resources/ex.php4?item=p305/pcr  [code sample]

Reacting to each keystroke rather than awaiting a new line #!/usr/bin/perl use POSIX; $| = 1; print "please press keys (q to quit)\n"; $numfile = fileno(STDIN); $keyboard = new POSIX::Termios (); $keyboard -> ... http://www.wellho.net/resources/ex.php4?item=p305/fc2  [code sample]

Unpacking characters #!/usr/bin/perl # data input while ($abc = ) { @chars = unpack("C" x length($abc),$abc); print ++$line,": @chars\n"; } __END__ ... http://www.wellho.net/resources/ex.php4?item=p305/file_in  [code sample]

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Reading data from STDIN and from files is plenty for many applications, but sometimes you'll need to read from the screen without echoing, process input even if the return key is not pressed, or check the keyboard to see if there's input available without pausing your program while the user responds.

This module is presented on Private Courses and Specially Run Courses only

askpw	Using ioctls and POSIX to provide a password entry system
fc2	Reacting to each keystroke rather than awaiting a new line
fi2	Reporting maximum field per line count
file_in	Unpacking characters
kb2	Giving the user a limited time to make an entry
kbcheck	select to check input availability
kbtest	If the user has started typing, wait for a whole line. Otherwise carry on
keyin	print out ASCII decimal equivalents of entries
pcr	Binary file copy