MPE/iX Error Messages Manual Vol 3 (32650-90880)

248 Chapter6
TurboIMAGE/XL V iii C 5
Library Procedure Error Messages
Library Procedure Error Messages
The success of each call to a TurboIMAGE/XL library procedure is reflected upon return to
the user by the condition code and the value of the return status in the first element of the
status area.
If the procedure fails to execute properly, the condition code is set to CCL (Condition Code
Less) and the return status is a negative integer. In this section, "Library Procedure File
System and Memory Management" describes the negative integers resulting from file
system and memory management failures, while "Library Procedure Calling Errors"
describes the negative integers resulting from calling errors and communications errors
respectively.
If the procedure operates properly but encounters an exceptional condition, such as
end-of-file, the condition code is set to CCG (Condition Code Greater) and the return status
is a positive integer. "Library Procedure Exceptional Conditions" describes the positive
integers resulting from exceptional conditions. If the procedure operates properly and
normally, the condition code is set to CCE (Condition Code Equal) and the return status is
zero.
In addition to the return status, all TurboIMAGE/XL library procedures put information
about the procedure call into the fifth through tenth elements of the status area. This
information may be useful in debugging your programs, because it describes the conditions
under which the particular results were obtained. This information is used by
DBEXPLAIN and DBERROR when they are interpreting the results of TurboIMAGE/XL
calls.
In a few cases this information is not returned by the TurboIMAGE/XL procedure because
it uses the same locations in the status area for returning other data. Specifically,
successful execution of DBFIND, DBGET, DBUPDATE, DBPUT, or DBDELETE puts
other information here as described in Chapter 5 of this manual. For all other returns from
a library procedure, the specified elements of the status area have the following contents:
Table 6-1. Status Area Changes for Native Applications
ELEMENT TurboIMAGE/V and Compatibility Mode TurboIMAGE/XL
5 PB-relative address of the caller. 0
6 Bits 6–15: Intrinsic number of called library
procedure. Bits 0–3: Zero or access mode in which
database is opened.
No change.
7 16-bit address of the database. First 16 bits of the
database address.
8 16-bit address of the data set name or qualifier. Second 16 bits of
database address.
9 Value of the mode parameter. No change.
10 PB-relative address of the library procedure or the
Compatibility Mode switch stub.
0