nt-lite/code/user/runtime/posix_start.c

// POSIX process startup. This file owns process-local POSIX personality initialization before main runs.

extern int main(void);
extern void exit(int status);
extern void PosixFdInit(void);

// Initializes POSIX process state and exits with main's return value.
void PosixStart(void) {
    PosixFdInit();
    int status = main();
    exit(status);
    for (;;) {}
}