Mach number a small area around the object's leading edge. (Fig.1b) Fig. 1. "Mach number in transonic airflow around an airfoil; M < 1 (a) and M > 1 (b)." When an aircraft exceeds Mach 1 (i.e. the sound barrier), a large pressure difference is created just in front of the aircraft. This abrupt pressure difference, called a shock wave, spreads backward and outward from the aircraft in a cone shape (a so-called Mach cone). It is this shock wave that causes the sonic boom heard as a fast moving aircraft travels overhead. A person inside the aircraft will not hear this.
Mach-O make backwards-compatible executables, the linker flag "-mmacosx-version-min=" can be used. Some versions of NetBSD have had Mach-O support added as part of an implementation of binary compatibility, which allowed some Mac OS 10.3 binaries to be executed. For Linux, a Mach-O loader was written by Shinichiro Hamaji that can load 10.6 binaries. As a more extensive solution based on this loader, the Darling Project aims at providing a complete environment allowing OS X applications to run on Linux. For the Ruby programming language, the ruby-macho library provides an implementation of a Mach-O binary parser and editor. Mach-O Mach-O, short for