03-01-2013
Quote:
Originally Posted by
sakurashinken
besides the process, process id and owner, I have no idea what these things are. Could someone explain?
Probably shared-memory segments or temporary files. It is hard to tell without the output surrounding it.
Quote:
Originally Posted by
sakurashinken
Also, what is /dev/random?
A device which produces a (pseudo-)random sequence of numbers, one every time you query it. For some things in UNIX one needs a random generator (for instance: the retransmission time offset if an Ethernet packet collides with another).
Random bits of "noise" is collected systemwide (i.e. from device drivers) in an "entropy pool". From this pool very high-quality random numbers are generated, but "/dev/random" will stop once the entropy pool is depleted until it is refilled. In most systems there is also a "/dev/urandom", which is will not block in this case, but produce "less random" (the numbers are more predictable).
I hope this helps.
bakunin
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LEARN ABOUT MOJAVE
random
RANDOM(4) BSD Kernel Interfaces Manual RANDOM(4)
NAME
random , urandom -- random data source devices.
SYNOPSIS
pseudo-device random
DESCRIPTION
The random device produces uniformly distributed random byte values of potentially high quality.
To obtain random bytes, open /dev/random for reading and read from it.
The same random data is also available from getentropy(2). Using the getentropy(2) system call interface will provide resiliency to file
descriptor exhaustion, chroot, or sandboxing which can make /dev/random unavailable. Additionally, the arc4random(3) API provides a fast
userspace random number generator built on the random data source and is preferred over directly accessing the system's random device.
/dev/urandom is a compatibility nod to Linux. On Linux, /dev/urandom will produce lower quality output if the entropy pool drains, while
/dev/random will prefer to block and wait for additional entropy to be collected. With Yarrow, this choice and distinction is not necessary,
and the two devices behave identically. You may use either.
The random device implements the Yarrow pseudo random number generator algorithm and maintains its entropy pool. The kernel automatically
seeds the algorithm with additional entropy during normal execution.
FILES
/dev/random
/dev/urandom
HISTORY
A random device appeared in the Linux operating system.
Darwin September 6, 2001 Darwin