When you start dbx,if you do not specify the -S option, dbx looks for the installed startup file, dbxrc, in the directory /installation_directory/lib. (The default installation_directory is /opt/sunstudio12.1 on Solaris platforms and /opt/sun/sunstudio12.1 on Linux platforms.) If your Sun Studio software is not installed in the default directory, dbx derives the path to the dbxrc file from the path to the dbx executable.
Then dbx searches for a .dbxrc file in the current directory, then in $HOME. You can specify a different startup file than .dbxrc explicitly by specifying the file path using the -s option. For more information, see Using the dbx Initialization File.
A startup file may contain any dbx command, and commonly contains the alias command, dbxenv command, pathmap command, and Korn shell function definitions. However, certain commands require that a program has been loaded or a process has been attached to. All startup files are loaded before the program or process is loaded. The startup file may also source other files using the source or .(period) command. You can also use the startup file to set other dbx options.
As dbx loads program information, it prints a series of messages, such as Reading filename.
Once the program is finished loading, dbx is in a ready state, visiting the “main” block of the program (for C or C++: main(); for Fortran 95: MAIN()). Typically, you set a breakpoint (for example, stop in main) and then issue a run command for a C program.