What does -a operator for String manipulation imply?
Eg:
if [ -a $string];then
Nothing comprehensible. This is invalid in a variety of ways. -a means "And", and is supposed to be used with two sub-statements, not a single string.
In ksh -a used in that fashion, means the same as -e ( True, if file exists ). In ksh93 this has become obsolete. There should be a space around the square brackets BTW.