Compiling COBOL code

Before you can run a program, you have to compile the source code.

You can configure the compilation using the following techniques:

• Compiler directives. You can control the way programs are compiled by using Compiler directives.

  You use directives to control the way the Compiler behaves. Normally, you need only a few directives. Most of the time, you use the default values. Note that setting some directives affects the default setting of other directives. For example, setting one directive might automatically unset another directive, and some directive settings are mutually exclusive.

• 32- and 64-bit compilation. You can also compile bit-specific output from the command line by using the cob32, cob64 or cobol (in conjunction with the COBMODE environment variable) commands.
• Linked resources. Linked resources enable you to link to sources that are outside the project, thereby saving you from copying the sources into the project, and enabling to share resources with others.
• Copybook locations. You can specify the location of the copybooks that your program refers to, if you keep them in different directories from the program. You can do this through the COBCPY environment variable.
• Temporary files used during compilation. Before compiling, you must ensure there is enough free space for the Compiler's temporary work files. You can specify the location where the Compiler puts its temporary files.
• Techniques for compiling quickly. Large applications comprising many programs can take significant time to compile. You can use various techniques to increase the speed of compilation.

The Compiler records errors with severity levels ranging from information messages to fatal errors which stop the Compiler working.

If the source code to be compiled contains characters beyond the standard 7-bit ASCII character set (for example, accented characters or characters belonging to multi-byte character sets), you must ensure that the locale has been set correctly, to match the source encoding of these characters. On UNIX, this means setting LANG, LC_CTYPE, or LC_ALL appropriately; each of these variables takes precedence over the former.

When you compile, the Compiler can produce executable code directly or object code. Object code is not executable, and has to be linked to the run-time system to create an executable file. If your project is set to build to .int and .gnt, by default the Compiler produces .int code during its syntax checking phase, and then it can produce .gnt code during the generating phase. You can modify this behavior from the project or the file properties.