CODEWITHSUNDEEP
clinuxmmapdev-null
user3489275
user3489275

Reputation: 411

mmap /dev/null for writing

Is it possible to mmap large amount of address space to /dev/null so all data written to it simply would be discarded?

I need to perform disk/network reads but I don't need readed data (I know, it sounds a little weird) and there is a lot of simultaneous read requests, so I don't want to waste "real" memory for this.

Upvotes: 1

Views: 1824

Answers (1)

lgeorget
lgeorget

Reputation: 470

In case it can help anyone trying to mmap /dev/null: this is actually impossible, and will return error ENODEV (no such device) which means (in this context) that this file cannot be mmaped.

This is because this is a special file for which no mmap operation is available. See http://lxr.free-electrons.com/source/drivers/char/mem.c#L768 for details.

Upvotes: 1

Related Questions