options/posix: initialize mem_file::_pos to zero
namespace mlibc {
mem_file::mem_file(char **ptr, size_t *sizeloc, void (*do_dispose)(abstract_file *))
-: abstract_file{do_dispose}, _bufloc{ptr}, _sizeloc{sizeloc}, _buf{getAllocator()} { }
+: abstract_file{do_dispose}, _bufloc{ptr}, _sizeloc{sizeloc}, _buf{getAllocator()}, _pos{0} { }
int mem_file::close() {
_update_ptrs();
