Re: [Pharo-users] Little how to

[stepharo]

Tx
This is a cool challenge


Le 3/3/16 13:08, Sven Van Caekenberghe a écrit :

On 03 Mar 2016, at 09:23, stepharo <steph...@free.fr> wrote:

Hi guys

for the mooc I would like have a list of how to that students should look in 
the system and implement.
The idea is to show to the participants that Pharo is open and that they can 
find information.
For example,
        - extracting a sprite from a png file
        - access a time service of the web

Time is soo simple that there is no real need for a true web service and such a 
service would be trivial anyway (yet I did not find any public/free ones).

Here is one way to do it:

| stream unixTime |
stream := nil.
[
        "RFC 868 TCP protocol https://en.wikipedia.org/wiki/Time_Protocol "
        stream := ZdcSocketStream openConnectionToHostNamed: 'time.nist.gov' 
port: 37.
        unixTime := (stream next: 4) asInteger ]
        ensure: [ stream ifNotNil: [ [ stream close ] on: Error do: [] ] ].
DateAndTime fromUnixTime: unixTime.


The real stuff is SNTP though

        http://en.wikipedia.org/wiki/Network_Time_Protocol
        http://tools.ietf.org/html/rfc2030

which is implemented in ZTimestamp and which can do much more:

   ZTimestampSNTPClient new remoteClock.

Sven

Now I would love to get your ideas and their solution.

Stef