INCDIR (Include Directory) Command Parameter

The Include Directory parameter (INCDIR) works with the Create Module and Create Bound Program compiler commands, allowing you to redefine the path used to locate include header files (with the #include directive) when compiling a source stream file only. The parameter is ignored if the source file's location is not defined as an IFS path via the Source Stream File (SRCSTMF) parameter, or if the full (absolute) path name is specified on the #include directive.

The parameter accepts a list of IFS directories. These directories are inserted into the include search path in the order they are entered.

The include files search path adheres to the following directory search order to locate the file:
Table 1. INCDIR Command Parameter
#include type Directory Search Order
#include <file_name>
  1. If you specify a directory in the INCDIR parameter, the compiler searches for file_name in that directory first.
  2. If more than one directory is specified, the compiler searches the directories in the order that they appear on the command line.
  3. Searches the directory /QIBM/include.
#include "file_name"
  1. Searches the directory where your current source file resides. The current source file is the file that contains the #include "file_name" directive.
  2. If you specify a directory in the INCDIR parameter, the compiler searches for file_name in that directory.
  3. If more than one directory is specified, the compiler searches the directories in the order that they appear on the command line.
  4. Searches the directory /QIBM/include.
For example, if you enter the following value for the INCDIR parameter: 
Include directory  . . . . . . . INCDIR         '/tmp/dir1'
                          + for more values     './dir2'
and with your source stream file you include the following header files: 
#include "foo.h"
#include <stdio.h>
The compiler first searches for a file "foo.h" in the directory where the root source file resides. If the file is found, it is included and the search ends. Otherwise, the compiler searches the directories entered INCDIR, starting with "/tmp/dir1". If the file is found, this file is included. If the directory does not exist, or if the file does not exist within that directory, the compiler continues to search in the subdirectory "dir2" within the current working directory (symbolized by "."). Again, if the file is found, this file is included, otherwise, because the directories in INCDIR path have now been exhausted, the default user include path (/QIBM/include) is used to find the header.

As for <stdio.h>, the same logic is followed in the same order, except the initial search in the root source directory is bypassed.