#include <stdio.h> #include <stdlib.h> #include "tests/sys_mman.h" int main(int argc, char **argv) { void *p1; void *p2; if ( ( p1 = mmap( 0, 4096, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0 ) ) == MAP_FAILED ) { perror( "aligned mmap failed" ); exit( 1 ); } if ( munmap( p1, 4096 ) != 0 ) { perror( "aligned munmap failed" ); exit( 1 ); } // This fails because MAP_FIXED is specified and p1+1 isn't page-aligned. // (On Linux, just non-page-alignment is enough for failure, but on Darwin // MAP_FIXED has to also be specified.) if ( ( p2 = mmap( p1 + 1, 4096, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0 ) ) == MAP_FAILED ) { perror( "unaligned mmap failed" ); exit( 1 ); } if ( munmap( p2, 4096 ) != 0 ) { perror( "unaligned munmap failed" ); exit( 1 ); } exit( 0 ); }