Shell and Utilities (XCU)
XCU1 is part of the Base Specifications, Issue 7.
XCU describes the shell and utilities that are available to application
programs on systems conformant to this volume of the Single UNIX
Specification. Readers are expected to be familiar with the XBD volume.
This volume is structured as follows:
Chapter 1 explains the relationship of XCU to other formal standards,
including the ISO C standard and also XSH. It also describes the utility
limits, grammar conventions, defaults used by the utility descriptions,
considerations for utilities in support of large files, and requirements
for built-in utilities.
Chapter 2 describes the command language-that is, the shell command
language interpreter-used in systems conformant to the Single UNIX
Specification. It also includes reference pages for the special built-in
utilities, organized alphabetically.
Chapter 3 describes a set of services and utilities that are implemented
on systems supporting the Batch Environment option.
Chapter 4 consists of reference pages for all utilities-other than
the special built-in utilities described in Chapter 2-available on
systems conforming to the Single UNIX Specification. These are in the
form of reference pages and are organized alphabetically.
- The acronym ``XCU'' derives from an earlier version of this volume of
the specification which was called ``Commands and Utilities''.