B Operating System Dependencies

Some details of COBOL programming vary from one system to another. This appendix is a collection of all system-specific issues regarding Pro*COBOL. References are provided, where applicable, to other sources in your document set.

B.1 System-Specific References in this Manual

System-specific references are described below, grouped by subject area.

B.1.1 COBOL Versions

The Pro*COBOL Precompiler supports the standard implementation of COBOL for your operating system (usually COBOL-85 or COBOL-74). Some platforms may support both COBOL implementations. Check your Oracle system-specific documentation.

B.1.2 Host Variables

How you declare and name host variables depends on which COBOL compiler you use. Check your COBOL user's guide for details about declaring and naming host variables.

B.1.2.1 Declaring

Declare host variables according to COBOL rules, specifying a COBOL datatype supported by Oracle. Table 4-6, "Host Variable Declarations " shows the COBOL datatypes and pseudotypes you can specify. However, your COBOL implementation might not include all of them.

B.1.2.2 Naming

Host variable names must consist only of letters, digits, and hyphens. They must begin with a letter. They can be any length, but only the first 30 characters are significant. Your compiler might allow a different maximum length.

Due to a Pro*COBOL limitation, when interacting with SQLLIB (C routines), some unpredictable results may occur unless boundaries for host variables are properly aligned. Refer to your COBOL documentation for specific information on defining host variable boundary alignment. Work-arounds could include:

Manual alignment using FILLER
FORCE the boundary by using 01 level entries
If the data source is third party code, then use temporary variables at 77 level entries or 01 level entries, and use those as host variables.

B.1.3 INCLUDE Statements

You can INCLUDE any file. When you precompile your Pro*COBOL program, each EXEC SQL INCLUDE statement is replaced by a copy of the file named in the statement.

If your system uses file extensions but you do not specify one, the Pro*COBOL Precompiler assumes the default extension for source files (usually COB). The default extension is system-dependent. Check your Oracle system-specific documentation.

If your system uses directories, you can set a directory path for included files by specifying the precompiler option INCLUDE=path. You must use INCLUDE to specify a directory path for nonstandard files unless they are stored in the current directory. The syntax for specifying a directory path is system-specific. Check your Oracle system-specific documentation.

B.1.4 MAXLITERAL Default

With the MAXLITERAL precompiler option you can specify the maximum length of string literals generated by the precompiler, so that compiler limits are not exceeded. The MAXLITERAL default value is 1024, but you might have to specify a lower value.

For example, if your COBOL compiler cannot handle string literals longer than 132 characters, specify "MAXLITERAL=132." Check your COBOL compiler user's guide. For more information about the MAXLITERAL option, see Chapter 14, "Precompiler Options"

B.1.5 PIC N or Pic G Clause for Multi-byte Globalization Support Characters

Some COBOL compilers may not support the use of the PIC N or PIC G clause for declaring multibyte Globalization Support character variables. Check your COBOL user's guide before writing source code that uses these clauses to declare multibyte character variables.

B.1.6 RETURN-CODE Special Register May Be Unpredictable.

The contents of the RETURN-CODE special register (for those systems that support it) are unpredictable after any SQL statement or SQLLIB function.

B.1.7 Byte-Order of Binary Data

On some platforms such as NT, the COBOL compiler reverses the byte-ordering of binary data. See your platform-specific documentation for the COMP5 precompiler option.