output_length.i4.v = str_tail_c(source_string.i1a.r, length.i4.v,
					output_string.i1a.r, tail_length.i4.v,

	This routine extracts a the tail of a string.

	source_string	source string
	length		length of source string
	output_string	buffer to copy extracted string to (It must be long
			enough to hold the extracted string plus a null
	tail_length	length of desired tail
	options		option flags
			(STR_OPT_NONE -> no options selected)

	This function returns status values as follows:

	CLIB_INVARG		invalid string or tail length
	otherwise		number of characters extracted

	This function requires the following include files:

	cbslib_h, acnet_errors_h

	Related functions:

	str_trim_c, str_trim_characters_c, str_extract_line_c, str_num_lines_c,
	str_get_value_c, strtok

	C/C++ usage:

	static const char	source_string[] = "Extract the tail";
	char	output_string[5];
	int	status;
	int	length = 0;
	int	tail_length = 4;
	unsigned int	options = STR_OPT_NONE;

	status = str_tail_c(source_string,length,output_string,tail_length,