If EnvName is the same as a subcommand handler already registered with RexxRegisterSubcomDll, RexxRegisterSubcomExe returns RXSUBCOM_DUP. This is not an error condition. RexxRegisterSubcomExe has successfully registered the new subcommand handler.
A REXX procedure can register dynamic link library subcommand handlers with the RXSUBCOM command. For example:
/* register Dialog Manager */
/* subcommand handler */
'RXSUBCOM REGISTER ISPCIR ISPCIR ISPCIR'
Address ispcir /* send commands to dialog mgr */
The RXSUBCOM command registers the Dialog Manager subcommand handler ISPCIR as routine ISPCIR in the ISPCIR dynamic link library.