+The passwd/group files have the following size restrictions:
+- maximum number of entries: '2^64-1' (uint64_t)
+- maximum passwd entry size: 65543 bytes (including newline)
+- maximum group entry size: 65535 bytes (including newline, only one member)
+- maximum members per group: depends on the user name length,
+ with 9 bytes per user: 5460 users
+- `nsscash` checks for these restrictions and aborts with an error if they are
+ violated
+