stdsyms(5) File Formats Manual stdsyms(5)
NAME
stdsyms - description of named defines and other specifications for namespace from HP-UX header files
DESCRIPTION
is a description of "named defines" and other specifications that must be set by the application to obtain the appropriate namespace from
the HP-UX header files.
HP-UX header files are organized in a manner that allows for only a subset of the symbols available in that header file to be visible to an
application that conforms to a specific standard. The ANSI-C, POSIX.1, POSIX.2, XPG4 and subsequent enhanced versions of ANSI-C/POSIX/XPG
each reserve a certain set of symbols for that standard's namespace. In addition, the HP-UX implementation of XPG3 and the "OSF AES/OS"
provides for a clean namespace although this is not a specific requirement of those standards.
The following rules apply in determining what symbols are reserved for any standard. These symbols are reserved for the standard and for
use by the implementation, and must be either avoided altogether, or used exactly as defined by the specified standard.
o All symbols defined by the desired standard are reserved. Refer to the appropriate standards documentation for a complete list of
reserved symbols.
o All symbols beginning with an underscore followed by another underscore or an uppercase letter are reserved for the implementation.
o All external identifiers beginning with an underscore are reserved for the implementation.
The following is a list of feature test macros which must be defined to obtain the appropriate namespace from the header files.
This symbol is automatically defined by the ANSI-C preprocessor and is automatically defined when specifying an ANSI-C compile Using the
strict ANSI option requests a pure ANSI-C namespace, which is the smallest subset of the HP-UX namespace available. The option also
enables the inclusion of ANSI-C-style function prototypes for increased type checking. Note that the default namespace when using the
option is the ANSI-C namespace; therefore a broader namespace must be requested if it is desired.
This symbol is automatically defined by the
ANSI-C preprocessor on some implementations. If defined, it indicates the version of the standard it is complying with.
As documented in the IEEE POSIX.1 standard, the programmer is required
to define the feature test macro to obtain the POSIX.1 namespace and POSIX.1 functionality. This feature test macro can be defined,
either by using compiler options or by using directives in the source files before any directives. Note that the default POSIX
namespace is the POSIX.1-1990 namespace. It is necessary to define the feature test macro in addition to the macro in order to
obtain the POSIX.1-1988 namespace.
As documented in the IEEE POSIX.2
standard, the programmer is required to define the feature test macro with a value of 2 to obtain the POSIX.1 and POSIX.2 namespaces
and functionality. This feature test macro can be defined, either by using compiler options or by using directives in the source
files before any directives.
As documented in the X/Open Portability Guide
the programmer is required to define the feature test macro to obtain X/Open functionality. This feature test macro can be defined,
either by using compiler options or by using directives in the source files before any directives. Although XPG3 does not specify
any namespace pollution rules, XPG4 and its subsequent versions have instituted such rules. Therefore, the HP-UX operating system
provides clean namespaces whenever is defined.
The current default X/Open namespace is that corresponding to XPG4. Broader namespace can be requested by setting to a value as
specified by the standard document.
As documented in the XPG, the programmer is required
to define the feature test macro to obtain namespace and functionality. This feature test macro can be defined either by using com-
piler option or by using directives in the source files before any directives.
As documented in the "OSF AES/OS"
standard, the programmer is required to define the feature test macro to obtain OSF functionality. This feature test macro can be
defined, either by using compiler options or by using directives in the source files before any directives. Although the AES does
not specify any namespace pollution rules, the other standards have instituted such rules. Therefore HP-UX provides a clean names-
pace whenever is defined. Use of is strongly discouraged as this functionality will be removed in a future release of HP-UX.
The programmer can define the
feature test macro to obtain the HP-UX namespace and complete HP-UX functionality. Note that the HP-UX namespace is currently a
superset of all of the above mentioned namespaces. When using the compiler with default options or the compiler with compatibility-
mode options command without the option), the HP-UX namespace is provided by default (see cc(1)). The programmer must request one
of the other namespaces as described above to obtain the appropriate subset of the HP-UX namespace. When using the strict ANSI-C-
mode compiler the programmer must specifically request a broader namespace.
The feature test macro can be defined, either by using compiler options or by using directives in the source files before any direc-
tives.
The following is a list of miscellaneous feature test macros that provide various additional features.
This symbol is automatically defined by the HP C++ compiler. Defining this macro enables the C++ function prototypes in system header
files.
The default namespace for HP C++ is the ANSI-C namespace. To obtain another namespace define the appropriate feature test macro.
HP C++ uses the ANSI-C preprocessor by default. To get the compatibility mode preprocessor, use the option of the command (see
cc(1)). The compatibility mode preprocessor uses the HP-UX namespace
This feature test macro should be defined
when the namespace is required. It should be used in conjunction with the macro if the default namespace is not desired.
This macro is defined automatically whenever or is requested.
The feature test macro is provided so that the programmer can obtain the XPG3 namespace, since it differs slightly from the namespace.
In order to obtain the XPG3 namespace, the programmer must define both the and feature test macros. The and feature test macros can
be defined, either by using compiler options or by using directives in the source files before any directives. Use of this macro is
strongly discouraged as this functionality will be removed in a future release of HP-UX.
The feature test macro is defined automatically if the programmer has requested the XPG4 namespace (that is, defined but not some other
conflicting namespace such as
The macro can be defined when using the compatibility mode compiler to obtain SVID2 function return types in the HP-UX namespace. The
default return types of many functions have since been changed in the HP-UX operating system to align with the ANSI-C, POSIX,
X/Open, and OSF standards. Use of this macro is strongly discouraged as this functionality will be removed in a future release of
HP-UX.
The SVID3 macro can be defined to obtain SVID3 function prototypes.
The compiler flag, needs to be defined to indicate that an application is written to meet SVID3 requirements. At the time the func-
tion prototypes were introduced in ANSI C, the functions exposed by this flag were only defined in SVID3.
SEE ALSO
cc(1), cpp(1), pathconf(2), sysconf(2), standards(5).
stdsyms(5)