CompletionStrncmpFunc
Specifies the type of the function passed to g_completion_set_compare(). This is used when you use strings as #GCompletion items.
param
s1
string to compare with @s2.param
s2
string to compare with @s1.param
n
maximal number of bytes to compare.return an integer less than, equal to, or greater than zero if the first @n bytes of @s1 is found, respectively, to be less than, to match, or to be greater than the first @n bytes of @s2.