RE: TCP/IP sockets - Getservbyname

[Chris Bipes <ChrisB@xxxxxxxxxxxxxxx>]

Thank You Scott.  You are a life savior.  Now all I need is a book, "C for
RPG programmers".  If only IBM have the socket function headers in RPG as
well as C.  When I am finished, I plan on posting what We have translated.

Christopher K. Bipes            mailto:ChrisB@Cross-Check.com
Sr. Programmer/Analyst          mailto:Chris_Bipes@Yahoo.com
CrossCheck, Inc.                http://www.cross-check.com
6119 State Farm Drive           Phone: 707 586-0551 x 1102
Rohnert Park  CA  94928         Fax: 707 586-1884



-----Original Message-----
From: Scott Klement [mailto:infosys@klements.com]
Sent: Thursday, July 22, 1999 3:47 PM
To: RPG400-L@midrange.com
Subject: Re: TCP/IP sockets - Getservbyname


Hi Chris...

Whats actually in the servent structure will be the pointer data,
not a null terminated string.   In other words, the pointer returned
by getservbyname does not start with a null-terminated character
string, but rather with the address of another area of memory.

What makes it even more fun is the s_aliases subfield in the
servent structure.   Its not just a pointer, but a pointer to
an array of pointers!  (variable-length, too)

The gethostbyname (which I use almost constantly) works the same
way, so if you're familiar with that, maybe that'll help you :)

Tell ya what, I'll include some example code (at the bottom of this
message) that shows the use of the getservbyname function.   (This
code has been tested, and it works on my system...)

Please keep in mind that these things ARE case-sensitive.  In other
words, if you use my example code, and do:

CALL PGM(WHATEVER) PARM('telnet' 'tcp')

This WILL work, but:

CALL PGM(WHATEVER) PARM('telnet' 'TCP')

this won't.   The service is 'tcp' not 'TCP'

Hope that helps...

Scott Klement
Information Systems Manager
Klement's Sausage Co, Inc.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* This is the RPG/400 Discussion Mailing List!  To submit a new         *
* message, send your mail to "RPG400-L@midrange.com".  To unsubscribe   *
* from this list send email to MAJORDOMO@midrange.com and specify       *
* 'unsubscribe RPG400-L' in the body of your message.  Questions should *
* be directed to the list owner / operator: david@midrange.com          *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *