Description

This function has the following rules:

• If both UTF-8 strings are NULL or 0-length, 0 is returned.

• If one of the strings is NULL or 0-length, the NULL or 0-length string is smaller.

• If one or both of the strings are not UTF-8, system provided strcasecmp is used.

• If one of the two strings contains no 8-bit characters, strcasecmp is used.

• The strings are compared after they are converted to lower-case UTF-8.

• Each character is compared from the beginning.

  Evaluation occurs in this order:

• If the length of one character is shorter then the other, the difference of the two lengths is returned.

• If the length of the corresponding characters is the same, each byte in the characters is compared.

• If there is a difference between two bytes, the difference is returned.

• If one string is shorter then the other, the difference is returned.