>>15
1. Strings (note: string.h, save for mem*, is shit).
2. Unicode. SEMANTICS MOTHERFUCKER, DO YOU USE THEM? Also, specifying Unicode support wouldn't hurt. Also, this "multibyte" mess is shit. Decent UTF-8, UTF-16 and UTF-32 support is a must.
3. Decently thought out functions (scanf? gets? strtok?) that have more functionality, less OH EXPLOITABLE owl.
4. time.h is shit, throw away and redo.
5. Half of stdio.h sucks.
6. Missing standard OS interface, even for the fucking filesystem! There's rename but there's no glob/findfirst? Most of unistd should have been specified as part of the standard library.
7. Missing basic libraries everybody writes for every fucking project: buffers and dynamic lists, sorted or not, doubly linked lists too.
8. Dictionaries (hashes) would also be of great help, and that's what a standard library is about.
9. Missing regular expressions. Something like PCRE, only with an usable API would be great.
10. NETWORK MOTHERFUCKER, BSD sockets need to be specified as part of the standard library too.
11. Portable threads, where are they. I'm also missing semaphores and IPC.
12. Higher-level utilities would be good too: template for a socket server, HTTP client, FTP client, SSL, AES, DES, MD5, SHA1, SHA-256, SMTP, POP, IMAP, RFC 822, MIME, Base64, quoted-printable, HTML quoting, URI handling, SAX, DOM, XPath query, INI files, getopt, platform-independent application configuration, platform introspection...
13. All you can do is stdin/stdout hacks. Missing ncurses-like library for generalized character-based Unicode terminals.
14. Missing platform-agnostic UI toolkit to allow simple, portable character-mode or graphics-mode interfaces.
15. Missing standard, platform agnostic low-level core multimedia services. Something like SDL.
16. Optional but standard garbage collector.
Think how would things be if they had equipped C with a decent standard library; one that allows you to write more than stdin/stdout lumps of horribly vulnerable crap in a standard fashion. Perhaps we wouldn't have Java, because the C standard library would have grown to do what it does in a standard, portable way. Most of POSIX should really have been C. Think how great would things be if we had a portable, usable, useful out-of-the-box C that doesn't require a gazillion of libraries before you can start doing anything useful with it.