Chapter 1 Getting Started
6 Setup
1.5 Setup
These procedures are for setting up this system when it has just been installed or for altering basic
settings.

Setting command path

Unix uses the environment variable PATH when searching for executable files. Setting up this variable
properly allows users to omit the directory name for commands and run them using their base names
only.
If this system has been installed in /usr/local/bin, for example, adding the directory /usr/local/bin to the
PATH environment variable permits the use of the command name only for the commands in this
system.
Under Unix, most users initialize environment variables via a start-up file named .cshrc and located in
the user's home directory. If this is the case, use an editor to modify the PATH variable setting in this
start-up file.
To put the changes into effect, either log out and then log in again or use the source command to
execute the contents of .cshrc.

Start-up files

The assembler and linker start by reading start-up files which contain statements for initializing start-
up variables.
The assembler start-up file (.as103rc) contains statements specifying the following three items.
1. The default language and character coding scheme for messages from the assembler
2. The radix notation used for numbers
3. The default toggle switch setting for optimization
The linker start-up file (.ld103rc) contains statements specifying the following eight items.
1. The language and character coding scheme for messages from the linker
2. A toggle controlling output of debugging information to the executable file
3. A toggle controlling output of the symbol table to the executable file
4. A toggle controlling output of DATA sections to the executable file
5. A toggle controlling output of a map file
6. A toggle controlling output of an executable file when there are errors
7. A library file
8. A directory searching for a library file
The assembler and linker search directories for these start-up files in the following order: the current
directory, the user's home directory, and the directory containing the executable. If they find such a file,
they use the contents to initialize their starting parameters. Otherwise, they set the parameters to their
default values. These default values are given in the section "Start-up file format."