Specifications

Portable and Interoperable Application Support
2.3 DECwindows Motif Programming Support
2.3.1 Linking and Navigation Capabilities with DEClinks
DEClinks services are included in the DECwindows Motif environment. They are
used for creating, managing, and traversing informational links between different
application-specific data. (DEClinks was formerly named LinkWorks.)
An application is said to be a hyperapplication if it participates in a
DECwindows DEClinks environment. Hyperapplications provide linking and
navigation capabilities to application end users through a new Link menu.
You can design new applications with DEClinks support or add DEClinks
support to existing applications. DEClinks services, with the DEClinks Manager
application, help organize information into a hyperinformation environment.
2.4 POSIX Programming Support
POSIX for OpenVMS offers VAX and AXP users the capability to develop and
run open, portable applications on the OpenVMS operating system. Applications
written to POSIX standards are portable across a wide range of UNIX and other
operating systems that support those same standards. Application developers
can develop and deploy their applications on any POSIX conformant system,
including VAX and AXP systems.
Most applications that strictly conform to the POSIX and X/Open standards and
draft standards can be developed on an OpenVMS VAX system with POSIX for
OpenVMS VAX or an OpenVMS AXP system with POSIX for OpenVMS AXP, and
then ported without modification to any other platform that supports the same
POSIX and X/Open standards and draft standards.
The converse is also true, that is, applications developed on platforms other than
OpenVMS systems that strictly conform to the POSIX and X/Open standards and
draft standards can be ported and run on an OpenVMS VAX or an OpenVMS
AXP system on which OpenVMS POSIX is installed. OpenVMS POSIX conforms
to IEEE Standard 1003.1-1990,XPG-3, and FIPS 151-1. It is also compliant
with drafts of 1003.2 (POSIX shell interface) and 1003.4 (real-time programming
interface).
OpenVMS POSIX application programs are written using the C language and
functions defined by the POSIX and X/Open standards and draft standards.
OpenVMS POSIX supports the POSIX 1003.1 standard for C bindings, which
incorporates ANSI C and includes a series of system services. POSIX system
services supported by OpenVMS POSIX include:
• Process creation, execution, and termination functions
• Process environment functions
• A series of POSIX functions that provide for file and directory operations
• I/O functions that include file I/O and creation of a pipe that serves as an
interprocess channel
• Terminal interface functions involving mapping of a set of control character
functions to sets of keys that are UNIX style or OpenVMS style
• Header files used for POSIX applications
The OpenVMS POSIX shell complies with a draft of POSIX 1003.2. The shell is
based on the Korn shell, and it includes common UNIX commands and utilities,
including make and c89 (the POSIX interface to the compiler and linker, which is
analogous to the cc command in UNIX).
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