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HP OpenVMS Systemsask the wizard |
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The Question is: In COBOL, when an '*' is moved to a pic 9 field what conversion is done and what value is now in that pic 9 field? The Answer is :
identification division.
program-id. w3688.
environment division.
data division.
working-storage section.
01 w1.
02 w2 pic 9 value 5.
01 w3 pic 9 value 6.
procedure division.
p0. move '*' to w1.
display w2 with conversion.
move '*' to w3.
display w3 with conversion.
stop run.
From a syntax perspective, you can do a straightforward move to the pic
9 field, and the Compaq COBOL compilers on VAX and Alpha will diagnose
the invalid move at compile time (move to w3). However, many
programmers use a backdoor approach (move to w1) for many different
reasons. The bottom line is that '*' is invalid decimal data, and the
results with invalid decimal data are undefined. The undefined results
are not 100% consistent between VAX and Alpha. In some cases the VAX
hardware does invalid decimal data checking at run time. We added
/CHECK=DECIMAL on Alpha to handle some of these cases, but the
operation of /CHECK=DECIMAL on Alpha is not 100% compatible with VAX
hardware. Note that /CHECK=DECIMAL on Alpha operates when the invalid
data is actually used (display with conversion) and not during the
move.
Compaq COBOL for OpenVMS VAX
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$ cobol w3688
12 move '*' to w3.
1
%COBOL-E-ERROR 135, (1) Invalid character in nonnumeric literal moved to numeric item
%COBOL-E-ENDDIAGS, COB$USER2:[BRAFFITT.WORK]W3688.COB;1 completed with 1 diagnostic
$ link w3688
%LINK-W-WRNERS, compilation warnings
in module W3688 file COB$USER2:[BRAFFITT.WORK]W3688.OBJ;1
$ run w3688
Compaq COBOL for OpenVMS Alpha
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$ cobol w3688
move '*' to w3.
.............^
%COBOL-E-INVCHAR, Invalid character in nonnumeric literal moved to numeric item
at line number 12 in file COB$USER2:[BRAFFITT.WORK]W3688.COB;1
%COBOL-E-ENDDIAGS, COB$USER2:[BRAFFITT.WORK]W3688.COB;1 completed with 1 diagnostic
$ link w3688
$ run w3688
$ cobol w3688/check=decimal
move '*' to w3.
.............^
%COBOL-E-INVCHAR, Invalid character in nonnumeric literal moved to numeric item
at line number 12 in file COB$USER2:[BRAFFITT.WORK]W3688.COB;1
%COBOL-E-ENDDIAGS, COB$USER2:[BRAFFITT.WORK]W3688.COB;1 completed with 1 diagnostic
$ link w3688
$ run w3688
%SYSTEM-F-DECINV, decimal invalid operand, PC=00000000000301D4, PS=0000001B
%TRACE-F-TRACEBACK, symbolic stack dump follows
image module routine line rel PC abs PC
W3688 W3688 W3688 11 00000000000001D4 00000000000301D4
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