6.4 Translation Rules for Strings
When planning the interaction between the ATMI platform and host applications, consideration must be given to the programming languages in which the applications are written. A character string is represented differently in the COBOL language than in the C language and associated ATMI platform VIEW buffer. The following listing demonstrates the three ways that the same two strings are coded (string1 and string2).
Listing Three Representations of Strings
C Structure:
struct text
{
char rbufsize[5];
char testnum[2];
char sendnum;
char sysid[4];
char textfld[10];
char string1[10];
char string2[16];
};
VIEW text
#type cname fbname count flag size null
char rbufsize - 5 - - -
char testnum - 2 - - -
char sendnum - 1 - - -
char sysid - 4 - - -
char textfld - 10 - - -
string string1 - 1 - 10 -
string string2 - 1 - 16 -
END
COBOL Record
01 TEXT.
05 RBUFSIZEPIC X(5).
05 TEXTNUMPIC X(2).
05 SENDNUM PIC X.
05 SYSID PIC X(4).
05 STRING1 PIC X(9).
05 STRING2PIC X(15).The listing shows that, in the C structure and VIEW buffer, the
sizes of string1 and string2 are
represented as 10 and 16 characters, respectively. However, in the
COBOL record, the sizes are 9 and 15 characters, respectively. This
incompatibility can cause code misalignment between C and COBOL
programs if not anticipated in the source code.
To avoid such incompatibilities, the Gateway provides a software option to control the mapping of string data between C and COBOL applications. This option enables you to automatically compensate for the differences in null termination and padding characteristics of the two languages.
Note:
The option affects string fields in the ATMI platform VIEW buffers only. STRING buffers are not affected by this switch.