- Entry:
- IO1
- VIT option:
- API
- Event:
- Application program request (Part 1)
- VIT processing module:
- ISTRACAP
- Control is returned to:
- ISTAPCRS or ISTOCCSM
This trace record shows API requests. It also provides the RPL information supplied by a VTAM® application program when it issues an RPL-based macroinstruction (such as SEND or OPNDST). The API routine ISTAICIR issues the TPIO SVC. ISTAPCTI gets control from the SVC, does validity checking, and queues the RPL to the PST request PAB. After the PST request PAB is dispatched, ISTAPCRS gets control and writes the entry, or calls ISTOCCSM to write the entry.
See z/OS Communications Server: SNA Programming for an explanation of the RPL fields.
The process that is started with this event will be completed
by a post (UP), or an exit (RE or UE). To correlate the two entries,
match the RPL addresses. 
- Byte (hex)
- Contents
- 00–02
- Record ID: C"IO1"
- 03
- RPL request type (RPLREQ)
- X'15'
- SETLOGON
- X'16'
- SIMLOGON
- X'17'
- OPNDST
- X'19'
- CHANGE
- X'1A'
- INQUIRE
- X'1B'
- INTRPRET
- X'1F'
- CLSDST
- X'22'
- SEND
- X'23'
- RECEIVE
- X'24'
- RESETSR
- X'25'
- SESSIONC
- X'27'
- SENDCMD
- X'28'
- RCVCMD
- X'29'
- REQSESS
- X'2A'
- OPNSEC
- X'2C'
- TERMSESS
- 04
- ID is the primary address space ID (ASID). This field is 0 if the ASID is greater than X'FF'.
- 05
- Exit definition (RPLEXTDS)
- 06
- Option code byte 4 (RPLOPT4)
- 07
- Option code byte 1 (RPLOPT1)
- 08–0B
- RPL address
- 0C–0F
- NIB address or CID
- 10
- Third byte of RH (RPLRH3)
- 11
- Send/receive type (RPLSRTYP)
- 12
- VTAM flags (RPLVTFL1)
- 13
- Post/respond flags (RPLVTFL2)
- 14
- RU chain position (RPLCHN)
- 15–17
- RU control codes (RPLCNTRL)
- 18–1B
- VTAM options (RPLOPTC2)
- 1C–1F
- VTAM options (RPLOPTC3)