| U_CONV_ERROR_STOP | Stop the conversion. This is the default mode. |
| U_CONV_ERROR_SKIP | Skip the character. |
| U_CONV_ERROR_SUBST | Substitute the character. The substituting character can be set with unicode_set_subst_char(). |
| U_CONV_ERROR_ESCAPE_UNICODE | Escape the faulty bytes and represent them in the Unicode character format. |
| U_CONV_ERROR_ESCAPE_ICU | Escape the faulty bytes and represent them in the ICU character format. |
| U_CONV_ERROR_ESCAPE_JAVA | Escape the faulty bytes and print them in the Java character format. |
| U_CONV_ERROR_ESCAPE_XML_DEC | Escape the faulty bytes and represent them in decimal format. |
| U_CONV_ERROR_ESCAPE_XML_HEX | Escape the faulty bytes and represent them in hexadecimal format. |