struct _iobuf { int _cnt; unsigned char *_ptr; unsigned char *_base; int _bufsiz; short _flag; char _file; } ; struct mallinfo { int arena; int ordblks; int smblks; int hblks; int hblkhd; int usmblks; int fsmblks; int uordblks; int fordblks; int keepcost; int mxfast; int nlblks; int grain; int uordbytes; int allocated; int treeoverhead; } ;