Before you execute a program that accesses a VSAM data set, you need to know:
Then you can write the required DD statement to access the data set:
//filename DD DSNAME=dsname,DISP=OLD|SHR
For example, if your file is named PL1FILE, your data set named VSAMDS, and you want exclusive control of the data set, enter:
//PL1FILE DD DSNAME=VSAMDS,DISP=OLD
To share your data set, use DISP=SHR.
Enterprise PL/I has no support for ISAM data sets.
To optimize VSAM's performance by controlling the number of VSAM buffers used for your data set, see the VSAM publications.