NAME

getarg - get command line arguments


SYNOPSIS

stat = getarg (n, array, maxsize)


integer n, maxsize
character array(ARB)
integer stat returned as length/EOF



DESCRIPTION

Getarg returns the "n"th argument to the current program in the
array "arg", one character per array element.
The argument is terminated by an EOS marker.
'Maxsize'
is passed as the maximum
number of characters array is prepared to deal with (including
the EOS);  getarg truncates the argument if necessary.
Getarg returns the length of the argument in "arg"
(excluding the EOS), or EOF
if "n" specified a non-existent argument.

On some systems, if "n" is zero, the name of the current program
is returned in "arg" and,
if "n" is -1, the function returns the number of
arguments on the command line.

Also, on some systems, command line arguments can only be passed
in a single case (upper or lower).
On these systems an escape mechanism may be necessary to
indicate case when specifying arguments.


IMPLEMENTATION


The implementation of 'getarg' may be quite different on different
operating systems.
Some systems allow only upper case (or lower case) on the command line;
they may limit size; they may not even provide access at all without
considerable contortions.

When implementing 'getarg', the designer should keep in mind that
a 'delarg' will also be needed.
One possible design would be to create a routine 'makarg', which would
pick up the arguments from the system, convert them to ascii strings,
handle any upper-lower case escape conventions, and store them in an
array.
'Getarg' could then access this array, stripping off any quoted strings
surrounding the arguments, and passing them along to the user.
'Delarg' could also access this array when removing reference to
arguments.

If it is absolutely impossible to pick up command line arguments from
the system, 'makarg' could be taught to prompt the user for them.

If the shell is implemented, 'getarg' (or perhaps 'markarg')
will have to be altered to read arguments as passed from the shell.


SEE ALSO

initst, delarg


DIAGNOSTICS

None