C99 draft N1256

Cite as: C99 draft N1256
Original: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf
sha256: 6b08dff0fab150aa86fc36cdef2bede7a73881f291ee096a16b7ab84cf7f91a1
Archived: https://web.archive.org/web/20261016225628/https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf
Accessed: 2026-10-20
Licence: none stated (a committee working draft, published by WG14)
Credit: The C standards committee, WG14.
Notes: The freely published draft that consolidates C99 and its three corrigenda; §7.20.2 (pp. 312–313) defines rand and srand and prints a portable example implementation. PDF sha256 6b08dff0fab150aa86fc36cdef2bede7a73881f291ee096a16b7ab84cf7f91a1.

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Golden Sun's `RPGRandom` is a linear congruential generator, $x \leftarrow 1103515245 x + 12345 (\mod 2^{32})$ (0x41C64E6D and 0x3039; the state `sRPGRNGState` is a 32-bit unsigned int on the GBA), returning `state >> 8` as an unsigned short: bits 8 to 23 of the state. `RPGRandom2` scales one result to 0 to 99, as RPGRandom × 100 >> 16 (computed). These are the constants of the C standard's example `rand`, which returns bits 16 to 30 instead. Pokémon Emerald's `Random` keeps the multiplier but adds 24691 and returns the top 16 bits; pret's `random.h` defines a second step, `ISO_RANDOMIZE2`, with Golden Sun's 12345.	`§7.20.2.2 ¶5, p. 312`	Code
The C standard defines `rand` as computing "a sequence of pseudo-random integers", and `srand` as starting a new sequence from a seed, so that the same seed repeats the same sequence.	`§7.20.2.1, p. 312§7.20.2.2, p. 312`	Publisher
The standard's example `rand` steps $x \leftarrow 1103515245 x + 12345$ and returns $⌊ x / 65536 ⌋ mod 32768$ .	`§7.20.2.2 ¶5, p. 312`	Publisher