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Powers

This strike lists c_calls, and the program denies every C call except write, so its one call to write builds.

power_deny_except/strike.zg
# Powers (owner, 2026-10-07): this strike lists `c_calls`, and the program denies every C call except
# `write`, so its one call to `write` builds. No std; CNC for C, and `vouch` for the `no_check`.

extern.C fn write ['fd': int32, 'buf': ptr[uint8], 'len': uint64] -> int64;

MAIN {
    let 'text' := "allowed
";
    no_check let 'n' := write[1, lend 'text', 8];
}
Output
allowed