What does it do? In this variant for specifying a pattern in the statements FIND and REPLACE , a character string posix is specified behind REGEX instead of a reference variable regex_ref . posix is a character-like expression position that can contain a valid POSIX regular expression. The occurrences are determined according to the leftmost-longest rule. Of all possible matches between the regular expression and the character string to be searched, the substring that starts at the furthest position to the left is selected. If there are multiple matches at this position, the longest of these substrings is selected.
