4    Process Environment

4.2    User Identification

4.2.3    Get Supplementary Group IDs

4.2.3.2    Description

The values of array entries with indexes larger than or equal to the value returned by getgroups() are not modified.

4.2.3.4    Errors

The system detects the following error for getgroups():

[EFAULT]

The gidsetsize and grouplist parameters specify an array that is partially or completely out of the address space of the process.

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4.2.4    Get User Name

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4.2.4.3    Returns

On the operating system, the return value from getlogin() points to static data.

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4.2.4.4    Errors

The system detects no errors for getlogin().

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4.4    System Identification

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4.4.1    Get System Name

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4.4.1.2    Description

On the operating system, the structure utsname contains the following members, formats, and ranges of values:

Table 4-1: Structure Members for uname() .NX r uname function structure members for .S 9

Member Name	Description	Format	Value
sysname	Operating system name	char[32]	The value is initialized from the kernel configuration file param.c.
nodename	The name of the operating system node that the network recognizes	char[32]	By default, this field is blank. It can be set using the sethostname() function.
release	Current release level of the operating system	char[32]	The major version number is initialized from the kernel configuration file version.major. The minor version number is initialized from the kernel configuration file version.minor.
version	Current version level of this release	char[32]	By default, this field is blank in the param.c file. The value is initialized from the kernel configuration file version.build.
machine	Name of the hardware type that the system is running on, for example, alpha	char[32]	By default, this field is set to "MACHINE". The value is initialized from the kernel configuration file param.c.

.S 10

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4.4.1.4    Errors

The uname() function returns -1 and sets errno to the corresponding value:

[EFAULT]

The name parameter points outside the process' address space.

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4.5    Time

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4.5.2    Process Times

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4.5.2.3    Returns

The operating system allows the return value from times() to overflow the possible range of type clock_t.

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4.6    Environment Variables

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4.6.1    Environment Access

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4.6.1.3    Returns

On the operating system, the return value from getenv() points to static data.

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4.7    Terminal Identification

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4.7.1    General Terminal Pathname

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4.7.1.3    Returns

If ctermid() is called with a NULL pointer, the string is generated in an area that is static.

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4.7.2    Determine Terminal Device Name

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4.7.2.2    Description

On the operating system, the return value of ttyname() points to static data.

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4.7.2.4    Errors

For the isatty() function, the following error conditions are detected:

[ENOTTY]

The specified file descriptor is not one that is open to a terminal device.

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4.8    Configurable System Variables

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4.8.1    Get Configurable System Variables

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4.8.1.2    Description

The operating system supports the following configurable system variables, in addition to those required in Table 4-2 of POSIX.1 and uses the following values for the name argument to sysconf() to query them.

Table 4-2: Configurable System Variables

Variable|name Value
{_AES_OS_VERSION}|{_SC_AES_OS_VERSION}
{ATEXIT_MAX}|{_SC_ATEXIT_MAX}
{PAGESIZE}|{_SC_PAGESIZE}
{PAGE_SIZE}|{_SC_PAGE_SIZE}
{PASS_MAX}|{_SC_PASS_MAX}
{_XOPEN_VERSION}|{_SC_XOPEN_VERSION}