Re: global pgm variable and file field with same name and attributes

David:

RPG IV is not case sensitive, so "gPgmId" is equivalent to "GPGMID".

The RPG compilers do not complain if you define the same variable name on a D-spec that is also defined in an externally described file, unless the type, length or decimal places are defined differently.

Perhaps your naming standards could be amended to help avoid this situation. For example, if a "g" prefix denotes a "global" variable, then "GPGMID" should not be permitted as a field name in an externally described database file. Or, you perhaps could change the "global" prefix to something like "g_" for internally declared variable names.

HTH,
Mark S. Waterbury

> On 1/25/2011 10:30 AM, David FOXWELL wrote:

Hi,

I hope someone will be able to explain this to me.

In this program, it looks like the programmer thought that coding gPgmId was different to GPGMID.

In the code, a file containing field GPGMID is read into display file field EPGMID. Then the global variable gPgmId is populated with EPGMID, read from a subfile.


D Main_procedure PI
D gPgmId S Like(....)

/free
CAllp subproc
gPgmId = EPGMID;
/end-free

In subproc :
EPGMID = GPGMID;


In the compiler listing, GPGMID appears once in the list of global variables. The source numbers next to it show that it does not seem to differentiate between the global variable declared by the programmer and the global field from the file.

So can anyone tell me what is actually happening in the program ? I think there is a danger that by coding gPgmId = EPGMID;
It is really initialising the file field GPGMID.















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