buf = calloc(huge, huge);
if (errno) perror("calloc failed");
printf("calloc(huge, huge) returned: %p\n", buf);
free(buf);
Its [errno's] value is significant only when the return value of
the call indicated an error (i.e., -1 from most calls; -1 or NULL
from most library functions); a function that succeeds is allowed
to change errno.If you write a program that relies on this behaviour you're going to have a hard to track down bug at some point.
The code should be something like this:
buf = calloc(huge, huge);
if (!buf)
perror("calloc failed");
printf("calloc(huge, huge) returned: %p\n", buf);
free(buf);