Declaring Fast Path application programs
You use the APPLCTN macro or the CREATE PGM command to declare the Fast Path application program name and whether it is a message-driven program. The PSB keyword is used to specify the PSB name, which is the same name as that of the message-driven program.
Declaring program processing
When you specify the PGMTYPE keyword value as TP, you designate the application program as message-driven. At the same time, you can specify FPATH=YES or FPATH=SIZE if you are certain the application program is always to be executed under Fast Path control. FPATH=SIZE establishes an Expedited Message Handler Buffer (EMHB) size for the application program. Specify FPATH=SIZE for the application program if its input or output message requirements are larger than the system default.
One special effect of explicitly declaring the application program to be a message-driven Fast Path program is that the subsequent TRANSACT macro automatically specifies the transaction to be Fast Path exclusive. The sequence of APPLCTN and TRANSACT macros also causes a routing code, with the same value as the transaction code, to be automatically generated in a routing code table; the routing code indicates that this is for a Fast Path-exclusive transaction.
If you do not explicitly declare the application program to be Fast Path, the sequence of APPLCTN and TRANSACT macros (when FPATH=SIZE or FPATH=YES is specified on the TRANSACT macro) identifies a Fast Path-potential transaction.
Most of the other APPLCTN keywords have the same use as for DL/I application programs. However, for the PGMTYPE keyword, the value of BATCH is not used for Fast Path programs. Also, the OVLY parameter and the option to declare a message class are not valid for Fast Path application programs. Parallel scheduling is specified with the keyword value SCHDTYP=PARALLEL if the message-driven program is to occupy more than one Fast Path dependent region for a balancing group.
Adding routing codes
You use the RTCODE macro or the CREATE RTC command to declare any routing codes that are to be associated with the program specified in the preceding APPLCTN macro statement. You need one RTCODE statement for each routing code. The name can be from 1 to 8 alphanumeric characters. It can be a duplicate of a transaction code or an LTERM name, but each routing code must be unique. These routing codes are in addition to those automatically generated by the APPLCTN-TRANSACT macro sequence.
You use the INQUIRY keyword to specify that, when this routing code is used to send a transaction to a balancing group, the program must use inquiry-only processing. INQUIRY=YES should be specified only for those transactions that do not cause a change to any database.