I don't think we should blame 3270 architecture for this behavior.
Rather, isn't the half-duplex nature of TSO a consequence of the TMP's (and ISPF's) use of SVC93? Specifically, the default "TGET WAIT" is what brings things to a halt and waits for the user to press an interrupt key. Optional use of "TGET NOWAIT" would allow the TMP or a CP (one such CP being ISPF) to test for the presence of input and, in its absence, continue issuing TPUT(s). It's been a long, long time since I looked at and/or played with this, so please correct me if I'm wrong. > Date: Fri, 21 Aug 2009 08:29:16 -0500 > From: [email protected] > Subject: Re: ISPF Counter > To: [email protected] > > I think this is an artifact that the 3270 data stream is really designed to > be "half duplex", like the old walkie-talkies. Each side tells the other > that it has control of the transmission. This is especially true in TSO. > Now, I do remember z/VM's or maybe CMS's control of the 3270 was more "full > duplex" like. > _________________________________________________________________ Windows Live: Make it easier for your friends to see what you’re up to on Facebook. http://windowslive.com/Campaign/SocialNetworking?ocid=PID23285::T:WLMTAGL:ON:WL:en-US:SI_SB_facebook:082009 ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
