Open System Services System Calls Reference Manual (G06.25+, H06.03+)

limits(4) OSS System Calls Reference Manual
NAME
limits - Specifies the system limits
SYNOPSIS
#include <limits.h>
DESCRIPTION
The limits.h header file defines symbolic names. These symbolic names represent:
• Implementation-dependent constants whose values set limits on system resources used
by applications in the OSS environment. These values are all at least as large as
minimum acceptable values set by the POSIX.1, POSIX.2, and XPG4 standards. See
Implementation-Dependent Constants
, later in this reference page.
• POSIX.1 and POSIX.2 minimum acceptable values. See POSIX-Defined Minimum
Values, later.
• Floating-point values for the two possible floating-point formats that a program can use.
The floating-point format is chosen at compilation time.
See the limits.h header file for the actual values of these limits in the HP implementation.
Some of the implementation-dependent constants have values that can increase at run time.
These runtime values can be determined at run time using the sysconf() function.
Other limiting values are available only at run time for one of the following reasons:
• The limit is pathname-dependent.
• The limit differs between compile time and run time.
These values are not specified in the limits.h header file. For completeness, they are listed under
Values Unknown at Compile Time, later in this reference page.
An application can use the fpathconf(), pathconf( ), and sysconf() functions to determine the
actual value of any limit at run time.
Implementation-Dependent Constants
The following values are defined in the limits.h header file. Some of these values are minimum
values that can increase at run time. Such values are indicated as "runtime-increasable."
BC_BASE_MAX
Maximum obase value allowed by the bc utility. This is a runtime-increasable
value. Use the sysconf() function to obtain the runtime value.
BC_DIM_MAX
Maximum number of elements permitted in an array by the bc utility. This is a
runtime-increasable value. Use the sysconf() function to obtain the runtime
value.
BC_SCALE_MAX
Maximum scale value allowed by the bc utility. This is a runtime-increasable
value. Use the sysconf() function to obtain the runtime value.
BC_STRING_MAX
Maximum length of a string constant accepted the bc utility. This is a runtime-
increasable value. Use the sysconf() function to obtain the runtime value.
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