C/C++ Programmer's Guide (G06.25+)

HP C/C++ Programmer’s Guide for NonStop Systems—429301-008
4-1
4 Using the C Run-Time Library
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Versions of the C Run-Time Library on page 4-1
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Input/Output Models on page 4-2, including ANSI model and alternate model I/O
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Mathematical Functions on page 4-6
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IEEE Floating-Point Arithmetic on page 4-7
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Differences Between Tandem and IEEE Floating-Point Formats on page 4-7
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Active Backup Programming Functions on page 4-8
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Environment-Specific Functions on page 4-10
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Changes Required to Interoperable Compilation Modules at D44 on page 4-10
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EDIT File Functions on page 4-11
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SQL Data-Type Conversion Functions on page 4-11
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Startup Information Retrieval Functions on page 4-11
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Miscellaneous HP Extension Functions on page 4-12
Versions of the C Run-Time Library
There are four versions of the C run-time library:
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Guardian TNS C run-time library
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Open System Services (OSS) G-series TNS C run-time library
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Guardian and OSS TNS/R native C run-time library
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Guardian and OSS TNS/E native C run-time library
The library version used depends on the environment (Guardian or OSS) and mode
(TNS or native) of a program.
Each library version provides the complete set of functions specified by the ISO/ANSI
C standard. The ISO/ANSI C standard allows implementations to vary in specific
instances. For details, see Appendix A, HP C Implementation-Defined Behavior
.
The OSS TNS and OSS native library versions and the Guardian native library
versions support additional functions specified by the XPG4 and XPG4 Version 2
specifications. For more information on standards compliance, see Complying With
Standards on page 1-19.
Regardless of the data model of a Guardian module, you can call ISO C standard
functions and HP extension functions. From Guardian modules using the 32-bit (wide)
data model, you can call many functions also specified in the XPG4 Version 1 or
Version 2 specifications (X/OPEN UNIX95) or the POSIX standard. From Guardian
modules using the 16-bit data model, you cannot call functions in the XPG4
specifications or the POSIX standard that are not also in the ISO C standard. (The ISO
C standard is a subset of the XPG4 specifications and the POSIX standard.)
The C run-time libraries also include HP extension functions for input and output, fault-
tolerant programming, SQL data-type conversion, EDIT file manipulation, and process
startup information retrieval.