Client software connects to SAP ASE by looking at the sql.ini file and the libtcl.cfg file and loading the specified Net-Library driver.
Each client:
Determines the name of the SAP ASE by finding the value of the DSQUERY environment variable.
Looks in the sql.ini file for an entry that matches the name of the server. If it cannot find a matching entry, the connection fails.
Looks in the libtcl.cfg file for an entry that matches the Net-Library driver name associated with the server entry in the sql.ini file. If the application cannot find such an entry, the connection fails.
Loads the specified Net-Library driver.
Uses the network connection information provided by the sql.ini file to connect to the server.