REG_EESCAPE        70 pcre/pcreposix.cpp   REG_EESCAPE, /* \ at end of pattern */
REG_EESCAPE        71 pcre/pcreposix.cpp   REG_EESCAPE, /* \c at end of pattern */
REG_EESCAPE        72 pcre/pcreposix.cpp   REG_EESCAPE, /* unrecognized character follows \ */
REG_EESCAPE       106 pcre/pcreposix.cpp   REG_EESCAPE, /* PCRE does not support \L, \l, \N, \U, or \u */