
\S pdp11 \S:  Examples

        if u3b15
    then cc -Du3b15 format.c -o format.o
        elif pdp-11
    then cc -Dpdp11 format.c -o format.o
        fi

    This shell program compiles the program in the file "format.c".  
    It puts the compiled version in "format.o".  The program checks if 
    the computer is an AT&T 3B15 computer, a pdp-11/70 or pdp-11/45.  If the 
    machine is a pdp-11/70 or a pdp-11/45, the second compile command 
    compiles "format.c".  The "Dpdp11" option to cc(1) causes only the 
    machine-dependent lines that pertain to pdp-11/70 or pdp-11/45 to be 
    executed so that "format.o" is correct for the machine it is compiled on.
    See the manual page for cpp(1) for an explanation of the "D" option.
