Explain the concept of Reentrancy in Operating systems.?-Os interview questions

Explain the concept of Reentrancy in Operating systems.?-Os interview questions
It is a useful, memory-saving technique for multiprogrammed timesharing systems. A Reentrant Procedure in O.S is one in which multiple users can share a single copy of a program during the same period. Reentrancy has 2 key aspects: The program code cannot modify itself, & the local data for each user process must be stored separately.
Thus, the permanent part is the code, & the temporary part is the pointer back to the calling program & local variables used by that program. Each execution instance is called activation. It executes the code in the permanent part, but has its own copy of local variables/parameters. The temporary part associated with each activation is the activation record. Generally, the activation record is kept on the stack.

iPhone Configuration Utility for Mac osx

About iPhone Configuration Utility 2.1 for Mac OS X

About iPhone Configuration Utility 2.1 for Mac OS X

iPhone Configuration Utility lets you easily create, maintain, encrypt, and push configuration profiles, track and install provisioning profiles and authorized applications, and capture device information including console logs.

Configuration profiles are XML files that contain device security policies, VPN configuration information, Wi-Fi settings, APN settings, Exchange account settings, mail settings, and certificates that permit iPhone and iPod touch to work with your enterprise systems. For instructions on how to use iPhone Configuration Utility, see the iPhone and iPod touch Enterprise Deployment Guide, available for downloading at:

Enterprise Deployment Guide - http://www.apple.com/support/iphone/enterprise/