RERR
RERR(REG_NOMATCH, "regexec() failed to match"),
RERR(REG_BADPAT, "invalid regular expression"),
RERR(REG_ECOLLATE, "invalid collating element"),
RERR(REG_ECTYPE, "invalid character class"),
RERR(REG_EESCAPE, "trailing backslash (\\)"),
RERR(REG_ESUBREG, "invalid backreference number"),
RERR(REG_EBRACK, "brackets ([ ]) not balanced"),
RERR(REG_EPAREN, "parentheses not balanced"),
RERR(REG_EBRACE, "braces not balanced"),
RERR(REG_BADBR, "invalid repetition count(s)"),
RERR(REG_ERANGE, "invalid character range"),
RERR(REG_ESPACE, "out of memory"),
RERR(REG_BADRPT, "repetition-operator operand invalid"),
RERR(REG_EMPTY, "empty (sub)expression"),
RERR(REG_EFATAL, "fatal internal error"),
RERR(REG_INVARG, "invalid argument to regex routine"),
RERR(REG_ECHAR, "illegal byte sequence"),
RERR(REG_ENOSYS, "function not supported"),
RERR(REG_STACK, "backtrack stack overflow"),
RERR(REG_ENSUB, "more than 9 \\( \\) pairs"),
RERR(REG_ENEWLINE, "\n found before end of pattern"),