Operating System Services

Operating system services are responsible for the management of platform resources, including the processor, memory, files, and input and output. They generally shield applications from the implementation details of the machine. Operating system services include:

• Kernel operations provide low-level services necessary to:
  • create and manage processes and threads of execution
  • execute programs
  • define and communicate asynchronous events
  • define and process system clock operations
  • implement security features
  • manage files and directories, and
  • control input/output processing to and from peripheral devices.
• Some kernel services have analogues described in the paragraph on Object Services, such as concurrency control services.
• Command interpreter and utility services include mechanisms for services at the operator level, such as:
  • comparing, printing, and displaying file contents
  • editing files
  • searching patterns
  • evaluating expressions
  • logging messages
  • moving files between directories
  • sorting data
  • executing command scripts
  • local print spooling
  • scheduling signal execution processes, and
  • accessing environment information.
• Batch processing services support the capability to queue work (jobs) and manage the sequencing of processing based on job control commands and lists of data. These services also include support for the management of the output of batch processing, which frequently includes updated files or databases and information products such as printed reports or electronic documents. Batch processing is performed asynchronously from the user requesting the job.
• File and directory synchronization services allow local and remote copies of files and directories to be made identical. Synchronization services are usually used to update files after periods of off line working on a portable system.

Copyright © The Open Group, 1998