IBM OS/390 User Manual

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Table 40. DOS PL/I Migration Considerations
Migration
Consideration
Comments
Dumps
The output produced by PLIDUMP is different when running
under OS/390 Language Environment.
Condition Handling
In general, PL/I condition handling continues to function in
the same way when running under OS/390 Language
Environment; however, you should consider the following:
The ERRCOUNT run-time option specifies how many
conditions of severity 2, 3, and 4 can occur before the
enclave terminates abnormally. The IBM-supplied
installation value for the ERRCOUNT run-time option is
ERRCOUNT(20). This value is not suitable for all PL/I
applications. To ensure that your application behaves
correctly, and is compatible with DOS PL/I behavior,
specify ERRCOUNT(0).
The diagnostic message for an ERROR condition is
issued only if there is no ERROR ON-unit established,
or if the ERROR ON-unit does not recover from the
condition by using a GOTO out of block. However, for
other PL/I conditions whose implicit action includes
printing a message and raising the ERROR condition,
the message is issued before control is given to an
established ERROR ON-unit.
Run-Time Message
Output - SYSPRINT
OS/390 Language Environment directs run-time message
output from PL/I programs to the file specified by the
OS/390 Language Environment MSGFILE run-time option,
instead of to the PL/I SYSPRINT file. User-specified output
is still directed to the PL/I SYSPRINT file. If you want
OS/390 Language Environment to handle this output,
specify the run-time option MSGFILE(SYSPRINT). When you
specify MSGFILE(SYSPRINT), SYSPRINT contains both
run-time messages and user-specified output.
Format and Content
of Messages in PL/I
The format and content of run-time messages is different
for PL/I applications running with OS/390 Language
Environment. If you have applications that analyze run-time
output, you should change them. Differences include:
The message number in the message prefix is now four
digits instead of three digits.
The message severity in the message prefix can now
be I, W, E, S, or C.
The message text of some mixed-case English and
Japanese messages has been enhanced.
DEPTHCONDLMT
Option
The default setting for the DEPTHCONDLMT option, both for
CICS and non-CICS, is DEPTHCONDLMT(10). The
recommended setting for PL/I applications, for compatibility
with DOS PL/I, is DEPTHCONDLMT(0).
Storage Report
The format of the run-time storage report generated by the
OS/390 Language Environment RPTSTG run-time option is
different than the format of the storage reports produced
by the DOS PL/I REPORT run-time option.
Chapter 17. Language Environment (LE)
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