erealloc
wchar_t *erealloc(wchar_t *, unsigned);
cp = erealloc(cp, (len+1)*sizeof (wchar_t));
*cp = erealloc(*cp, (length+1) * sizeof (wchar_t));
*bp = erealloc(*bp, *len * sizeof (wchar_t));
cp = erealloc(cp, (n+len+seplen+1) * sizeof (wchar_t));