IBM Tivoli NetView for z/OS Programming: Pipes - IBM notice

Usage Notes
Examples
PIPE LOOKUP
v Having any character other than an asterisk (*) as the second character, and
v Having the third and fourth characters CD.
Note: Z can be used to check a detail record that represents a wildcard
pattern. The intended use is to enable security checking of wildcard
patterns.
If a blank is specified for any of the three characters, x, y, orz, indicates to not
use that option to select matching records.
v LOOKUP requires two input streams and supports up to three output streams. If
an output stream is not connected, the data to be passed on that output stream
is discarded.
v LOOKUP must be able to read its secondary input until it disconnects. If it
cannot read its secondary input, the pipeline can clog.
For information about clogged pipelines, see “Clogged Pipelines” on page 346.
v When the length for the detail and reference records are different, and the
WILDCARD option is not used, the characters specified for the reference record
are searched for within the characters specified in the detail record. For example,
if LOOKUP 1.6 5.2 is specified, two characters of each reference record
beginning at character 5 are compared to the first 6 characters in the detail
record. Two consecutive characters within the first 6 characters of the detail
record matching the 2 characters specified in the reference records cause a
match. However, LOOKUP 1.2 6.4 searches for 4 characters of each reference
record in 2 characters of the detail record.
When the WILDCARD option is used, the pattern specified by the reference
record is compared to the data in the detail records. For a match to occur, the
data must match the pattern. All characters in the referenced data field are
significant, including blanks. A wildcard pattern with trailing blanks implies that
the detail record must have blanks in the same position. The pattern "AB*" is not
the same as "AB* ".
v Reference record line attributes such as color and line count are preserved.
However, message attributes such as MLWTO structure and AUTOTOKE are not
preserved.
v When APPEND is specified, LOOKUP appends both the data and line attributes
of the reference record to the detail record.
When the line attributes become inappropriately mixed within the output data
stream, for example a label coming after a data line, insert a COLLECT MAX 1
stage before writing the output data stream to the CONSOLE.
v Detail record line and message attributes are preserved in the output stream.
v Avoid duplicate reference records. LOOKUP processing cannot guarantee which
of the duplicate records is to be examined. Duplicate reference records must be
particularly avoided if the APPEND keyword is specified, because the record
selected by LOOKUP to be appended is unknown.
v Reference records passed to the third output stream might not be in the same
order as received on the secondary input stream.
Example: Comparing Values Contained in Two Stems
The following REXX fragment compares the stem old. to new. and creates three
new stems:
Chapter 2. Pipeline Stages and Syntax 161