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For 2023 (and 2024 ...) - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.

Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!

I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
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 signal if the user doesn't enter data within a certain time. The code's [here] if you want to have a look. But let me warn you ... it's one of those thisng that may be somewhat operating system dependent, even though most Perl code is pretty darned portable.
A correspondent writes: "try the code; it hangs after the first warning. The comeon signal handler needs to call the alarm and increment the counter because the code in the main loop that looks to do so is never reached when no entry is typed. a correction would look like [this] (good exercise for student, by the way, so thanks)"

Hmmm ... on the laptops that I'm working on today (Mac OS X / Perl 5.8.x) both versions work perfectly. The second version (from M.K.) illustrates his point, but with a degree of code duplication so it could really do with being tidied up ... and I have not yet tested it across a range of platforms. I'm posting links to both examples, and these notes, because waiting for a user input ... but only for a while, before carrying on ... is a very useful capability, and these notes may be of some help to the reader, even though I have not fully researched the story.

What is does remind me of is that saying:
"Compatible" = "99% Compatible" = "Incompatible"

and the need to check and recheck code across platforms, and HTML and JavaScript across browsers!
(written 2009-08-28)

Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
P305 - Perl - User Input
  [2213] Keyboard reading in Perl - character by character not line by line - (2009-06-01)
  [2876] Different perl examples - some corners I rarely explore - (2010-07-18)

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Looking ahead to the Autumn season of training and accommodation
Lua Regular Expressions
Giving up on user input - keyboard timeout in Perl
Checking the database connection manually
Object Oriented programming - a practical design example
Making variables persistant, pretending a database is a variable and other Perl tricks
Handling XML in Perl - introduction and early examples
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