#cmakedefine _LARGEFILE_SOURCE #cmakedefine _LARGEFILE64_SOURCE #cmakedefine _LARGE_FILES #cmakedefine _FILE_OFFSET_BITS ${_FILE_OFFSET_BITS} #include <sys/types.h> #include <stdio.h> #include <stdlib.h> int main(int argc, char **argv) { /* Cause a compile-time error if off_t is smaller than 64 bits, * and make sure we have ftello / fseeko. */ #define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62)) int off_t_is_large[ (LARGE_OFF_T % 2147483629 == 721 && LARGE_OFF_T % 2147483647 == 1) ? 1 : -1 ]; FILE *fp = fopen(argv[0],"r"); off_t offset = ftello( fp ); fseeko( fp, offset, SEEK_CUR ); fclose(fp); return 0; }