The format strings for printf(3C), sprintf(3C), scanf(3C), and sscanf(3C) might
need to be changed for long
or pointer arguments. For pointer
arguments, the conversion operation given in the format string should be %p to work in both the 32-bit and 64-bit environments. For example,
char *buf; struct dev_info *devi; ... (void) sprintf(buf, "di%x", (void *)devi);
produces the warning:
warning: function argument (number) type inconsistent with format sprintf (arg 3) void *: (format) int
Use the following code to produce clean results:
char *buf; struct dev_info *devi; ... (void) sprintf(buf, `di%p", (void *)devi);
For long
arguments, the long
size specification, l, should be prepended to the conversion operation character in
the format string. Furthermore, check to be sure that the storage pointed
to by buf
is large enough to contain 16 digits. For example,
size_t nbytes; ulong_t align, addr, raddr, alloc; printf("kalloca:%d%%%d from heap got%x.%x returns%x\n", nbytes, align, (int)raddr, (int)(raddr + alloc), (int)addr);
produces the warnings:
warning: cast of 64-bit integer to 32-bit integer warning: cast of 64-bit integer to 32-bit integer warning: cast of 64-bit integer to 32-bit integer
The following code will produce clean results:
size_t nbytes; ulong_t align, addr, raddr, alloc; printf("kalloca:%lu%%%lu from heap got%lx.%lx returns%lx\n", nbytes, align, raddr, raddr + alloc, addr);