fmemcmp man page
fmemcmp — fuzzy comparison of two memory areas
double fmemcmp(const void *data1, size_t size1, const void *data2, size_t size2);
The fmemcmp() function compares the two memory areas, the size1 bytes pointed to by data1 and the size2 bytes pointed to by data2.
The fmemcmp function returns a floating point value between 0.0 and FSTRCMP_IDENTICAL. A value of 0.0 means the memory areas are utterly un‐alike. A value of FSTRCMP_IDENTICAL means the memory areas are identical. A value of more than FSTRCMP_THRESHOLD (it lies between 0.0 and FSTRCMP_IDENTICAL) would be considered "similar" by most people.
A value of FSTRCMP_ERROR (always negative) indicates a malloc(3) failure.
fuzzy comparison of two memory areas
fuzzy comparison of two strings
compare memory areas
fstrcmp version 0.7
Copyright (C) 2009 Peter Miller
Peter Miller <email@example.com>
The comparison code is derived from the fuzzy comparison functions in GNU Gettext 0.17. The GNU Gettext comparison functions were, in turn, derived from GNU Diff 2.7.
Copyright (C) 1988-2009 Free Software Foundation
fmemcmpi(3), fstrcasecmp(3), fstrcmp(1), fstrcmp(3), fstrcmpi(3).