personal

In voice over IP (VoIP), a jitter buffer is a shared data area where voice packets can be collected, stored, and sent to the voice processor in evenly spaced intervals. Variations in packet arrival time, called jitter, can occur because of network congestion, timing drift, or route changes. The jitter buffer, which is located at the receiving end of the voice connection, intentionally delays the arriving packets so that the end user experiences a clear connection with very little sound distortion.

There are two kinds of jitter buffers, static and dynamic. A static jitter buffer is hardware-based and is configured by the manufacturer. A dynamic jitter buffer is software-based and can be configured by the network administrator to adapt to changes in the network's delay.

Ozeki VoIP SIP SDK contains dynamic jitter buffer technology. This technique is automatically used in the SDK, so you do not need and cannot turn it on or off, all your VoIP solutions will use this feature without any further method call or implementation.

From: http://www.voip-sip-sdk.com/p_372-voip-jitter-buffer-voip.html

http://dev.gentoo.org/~vapier/crt.txt

Mini FAQ about the misc libc/gcc crt files.

Some definitions:
PIC - position independent code (-fPIC)
PIE - position independent executable (-fPIE -pie)
crt - C runtime

crt0.o
Older style of the initial runtime code ? Usually not generated anymore
with Linux toolchains, but often found in bare metal toolchains. Serves
same purpose as crt1.o (see below).
crt1.o
Newer style of the initial runtime code. Contains the _start symbol which
sets up the env with argc/argv/libc _init/libc _fini before jumping to the
libc main. glibc calls this file 'start.S'.
crti.o
Defines the function prolog; _init in the .init section and _fini in the
.fini section. glibc calls this 'initfini.c'.
crtn.o
Defines the function epilog. glibc calls this 'initfini.c'.
Scrt1.o
Used in place of crt1.o when generating PIEs.
gcrt1.o
Used in place of crt1.o when generating code with profiling information.
Compile with -pg. Produces output suitable for the gprof util.
Mcrt1.o
Like gcrt1.o, but is used with the prof utility. glibc installs this as
a dummy file as it's useless on linux systems.

crtbegin.o
GCC uses this to find the start of the constructors.
crtbeginS.o
Used in place of crtbegin.o when generating shared objects/PIEs.
crtbeginT.o
Used in place of crtbegin.o when generating static executables.
crtend.o
GCC uses this to find the start of the destructors.
crtendS.o
Used in place of crtend.o when generating shared objects/PIEs.



General linking order:
crt1.o crti.o crtbegin.o [-L paths] [user objects] [gcc libs] [C libs] [gcc libs] crtend.o crtn.o

-Mforce-thumb 옵션을 추가한다

clock_gettime의 인자로는 MONOTONIC이어야 한다