Pull - IBM SC34-5764-01 Manual

PULL

PULL
Purpose
PULL
template_list
PULL reads a string from the program stack. If the program stack is empty, PULL then tries reading a line
from the current terminal input device. It is just a short form of the instruction:
PARSE UPPER PULL
The current head-of-queue is read as one string. Without a template_list specified, no further action is
taken (and the string is thus effectively discarded). If specified, a template_list is usually a single template,
which is a list of symbols separated by blanks or patterns or both. (The template_list can be several
templates separated by commas, but PULL parses only one source string; if you specify several
comma-separated templates, variables in templates other than the first one are assigned the null string.)
The string is translated to uppercase (that is, lowercase a–z to uppercase A–Z) and then parsed into
variables according to the rules described in the section on parsing (page 203). Use the PARSE PULL
instruction if you do not desire uppercase translation.
Notes:
1. The REXX/CICS implementation of the external data queue is the program stack. The language
processor reads a line from the program stack. If the program stack is empty, a terminal read occurs.
The program stack for you is in an RLS queue named \SYSTEM\rexxtnum\*PROGSTACK* where
rexxtrnum is an internal REXX task number.
2. If the PULL causes a read from the terminal, the variable PULLKEY is set upon completion of the
PULL command. It will contain the name of the aid key pressed in response to the PULL command (for
example: ENTER, PFKEY 1, PAKEY 1, MSR, PEN, or CLEAR).
For information on named queues, see the REXX List System LPULL command in section "LPULL" on
page 275.
Example:
Say 'Do you want to erase the file? Answer Yes or No:'
Pull answer .
if answer='NO' then say 'The file will not be erased.'
Here the dummy placeholder, a period (.), is used on the template to isolate the first word the user enters.
If the external data queue is empty, a console read is issued and the program pauses, if necessary, until a
line is complete.
The QUEUED built-in function (see page 190) returns the number of lines currently in the program stack.
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CICS TS for VSE/ESA: REXX Guide
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template_list