if ('A' <= *p && *p <= 'Z') *p += 'a' - 'A';
if (isupper (*p)) *p = tolower (*p);
void mutt_canonical_charset (char *dest, size_t dlen, const char *name){  size_t i;  char *p;  char scratch[LONG_STRING];  /* catch some common iso-8859-something misspellings */  if (!mutt_strncasecmp (name, "iso8859", 7) && name[7] != '-')    snprintf (scratch, sizeof (scratch), "iso_8859-%s", name + 7);  else if (!mutt_strncasecmp (name, "iso8859-", 8))    snprintf (scratch, sizeof (scratch), "iso_8859-%s", name + 8);  else    strfcpy (scratch, NONULL(name), sizeof (scratch));  for (i = 0; PreferredMIMENames[i].key; i++)    if (!mutt_strcasecmp (scratch, PreferredMIMENames[i].key))    {      strfcpy (dest, PreferredMIMENames[i].pref, dlen);      return;    }  strfcpy (dest, scratch, dlen);  /* for cosmetics' sake, transform to lowercase. */  for (p = dest; *p; p++)    if ('A' <= *p && *p <= 'Z')      *p += 'a' - 'A';}