POSIX.1-2024 defines a standard operating system interface and environment, including a command interpreter (or ``shell’’), and common utility programs to support applications portability at the source code level. It is intended to be used by both application developers and system implementors. POSIX.1-2024 comprises four major components (each in an associated volume): 1. General terms, concepts, and interfaces common to all volumes of POSIX.1-2024, including utility conventions and C-language… read more header definitions, are included in the Base Definitions volume of POSIX.1-2024. 2. Definitions for system service functions and subroutines, language-specific system services for the C programming language, function issues, including portability, error handling, and error recovery, are included in the System Interfaces volume of POSIX.1-2024. 3. Definitions for a standard source code-level interface to command interpretation services (a ``shell’’) and common utility programs for application programs are included in the Shell and Utilities volume of POSIX.1-2024. 4. Extended rationale that did not fit well into the rest of the document structure, containing historical information concerning the contents of POSIX.1-2024 and why features were included or discarded by the standard developers, is included in the Rationale (Informative) volume of POSIX.1-2024. The following areas are outside of the scope of POSIX.1-2024: --Graphics interfaces --Database management system interfaces --Record I/O considerations --Object or binary code portability --System configuration and resource availability POSIX.1-2024 describes the external characteristics and facilities that are of importance to application developers, rather than the internal construction techniques employed to achieve these capabilities. Special emphasis is placed on those functions and facilities that are needed in a wide variety of commercial applications. The facilities provided in POSIX.1-2024 are drawn from the following base documents: --IEEE Std 1003.1-2017 (POSIX.1-2017) --IEEE Std 1003.26-2003 (POSIX.26-2003). ISO/IEC 9899: 2018, Programming Languages -- C (C17) --ISO/IEC TR 24731-2: 2010, Programming languages, their environments and system software interfaces — Extensions to the C library — Part 2: Dynamic Allocation Functions --The Open Group Standard, 2021, Additional APIs for the Base Specifications Issue 8, Part 1 --The Open Group Standard, 2022, Additional APIs for the Base Specifications Issue 8, Part 2 read less

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This standard is applicable to the development and use of conformance testing methodologies for POSE standards. The generic test methods identified in this standard shall be used in conjunction with test methods identified for a specific standard. This standard is intended for use by working groups developing test methods for POSM standards, developers of POSM test methods, and users of POSIX test methods. The purpose of this standard is to define general rules for developing test assertions… read more and related test methods for measuring conformance of an implementation to POSE standards. Test methods may include POSM Conformance Test Suites (PCTS), POSE Conformance Test Procedures (PCTP), and audita of POSM Conformance Documents (PCD). Testing conformance of an implementation to a standard includes testing the claimed capabilities and behavior of the implementation with respect to the conformance requirements of the standard. Test methods are intended to provide a reasonable, practical assurance that the implementation conforms to the standard. Use of these test methods will not guarantee conformance of an implementation to the standard; that normally would require exhaustive testing (see 4.2.11, which is impractical for both technical and economic reasons. read less

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This standard defines a standard Ada language binding to ISO/lEC 9945-1: 1990 {2}, hereinafter referred to as "POSIX.1 [2]" to support application portability at the source code level. It is intended to be used by both application developers and system implementors. The focus of this standard the Ada interface to the is POSIX.1 {2} standard. The POSIX.1 {2} standard was initially defined using the C programming language. A language-independent definition of POSIX.1 {2} is under development, but… read more at this time has not achieved a level of definition suitable as a starting point for this document. This standard is comprised of three major components:- Definitions for terminology and concepts, and definitions and specifications that govern program structures, language-system interaction, and related requirements- Definitions of the specific Ada interfaces to POSIX.1 {2} system services presented in the form. of Ada packages- Interpretations of Ada semantics with respect to POSIX.1 {2} read less

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The purpose of this standard is to provide test equipment requirements and methods for testing the transmission characteristics of PCM telecommunications equipment, circuits, and systems. The test equipment requirements are intended to be suitable for certification, installation, pre-service, and out-of-service operational and in-service operational tests of the PCM transmission facilities. The PCM equipment that may be tested includes primary multiplex equipment containing A-D (Analog-Digital)… read more conversion devices, digital multiplex equipment, digital links, and digital sections. This document is currently limited to testing at the analog interfaces of the primary multiplex equipment and the digital interfaces at DS1, DS1C, DS2, and DS3 levels of the North American digital hierarchy. Synchronous multiplex equipment and equipment offering other than 64 kb/s coded voiceband channels (e.g., 32 kb/s voiceband coding, 256 kb/s program, or 64 kb/s data) are not covered in this standard. Signaling parameter measurement is outside the scope of this document. read less

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Software unit testing is a process that includes the performance of test planning, the acquisition of a test set, and the measurement of a test unit against its requirements. Measuring entails the use of sample data to exercise the unit and the comparison of the unit's actual behavior with its required behavior as specified in the unit's requirements documentation. This standard defines an integrated approach to systematic and documented unit testing. The approach uses unit design and unit… read more implementation information, in addition to unit requirements, to determine the completeness of the testing. This standard describes a testing process composed of a hierarchy of phases, activities, and tasks and defines a minimum set of tasks for each activity. Additional tasks may be added to any activity. This standard requires the performance of each activity. For each task within an activity, this standard requires either that the task be performed, or that previous results be available and be re-verified. This standard also requires the preparation of two documents specified in ANSI/IEEE Std 829-1983 [2] 1 . These documents are the Test Design Specification and the Test Summary Report. General unit test planning should occur during overall test planning. This general unit test planning activity is covered by this standard, although the balance of the overall test planning process is outside the scope of this standard. This standard may be applied to the unit testing of any digital computer software or firmware. However, this standard does not specify any class of software or firmware to which it must be applied, nor does it specify any class of software or firmware that must be unit tested. This standard applies to the testing of newly developed and modified units. This standard is applicable whether or not the unit tester is also the developer. read less

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This recommended practice describes a method for sizing both vented and valve-regulated lead-acid batteries in stand-alone PV systems. Installation, maintenance, safety, testing procedures, and consideration of battery types other than lead-acid are beyond the scope of this recommended practice. Sizing batteries for hybrid and grid-connected PV systems is beyond the scope of this recommended practice. Recommended practices for the remainder of the electrical systems associated with stand-alone PV installations are also beyond the scope of this recommended practice. Sizing examples are given for various representative system applications. Iterative techniques to optimize battery costs, which include consideration of the interrelationship between battery size, PV array size, and weather, are beyond the scope of this recommended practice.

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This standard defines the logical interface for interconnecting two different buses based on Futurebus+ and VME64 in a tightly coupled configuration. Such an interconnecting interface is called a Bridge. Interface between the Bridge and each of the buses is defined in accordance with the standard for the respective bus.

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This recommended practice provides information for selecting the proper circuit breaker for a particular application. This recommended practice helps the application engineer specify the type of circuit breaker, ratings, trip functions, accessories, acceptance tests, and maintenance requirements. It also discusses circuit breakers for special applications, e.g., instantaneous only and switches. In addition, it provides information for applying circuit breakers at different locations in the… read more power system and for protecting specific components. Guidelines are given for coordinating combinations of line-side and loadside devices. Acceptance testing and maintenance guidelines are provided so that reliable operation can be verified and maintained. This recommended practice does not cover the selection and application of circuit breakers such as marine circuit breakers and definite purpose circuit breakers. read less

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Procedures and test voltage values for factory, acceptance and maintenance testing of ESP cable systems are presented. Installation and handling practices are also covered. This procedure applies to cable systems rated 3 kV through 8 kV (phase to phase).

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This recommended practice establishes recommendations for three-conductor round and flat oil-well cables consisting of ethylene-propylene rubber (EPR) insulated copper conductors used in supplying three-phase ac electric power to submersible pump motors. These cables may also include additional coverings consisting of wraps, metallic armor or barriers, and/or nonmetallic jackets or sheaths selected on the basis of mechanical and environmental conditions.

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