Tribblix: manual page: getconf.1

GETCONF(1) User Commands GETCONF(1)

NAME

getconf - get configuration values

SYNOPSIS

/usr/bin/getconf, /usr/xpg4/bin/getconf, /usr/xpg6/bin/getconf
/usr/bin/getconf [-v specification] system_var

/usr/bin/getconf [-v specification] path_var pathname

/usr/bin/getconf -a

/usr/xpg4/bin/getconf [-v specification] system_var

/usr/xpg4/bin/getconf [-v specification] path_var pathname

/usr/xpg4/bin/getconf -a

/usr/xpg6/bin/getconf [-v specification] system_var

/usr/xpg6/bin/getconf [-v specification] path_var pathname

/usr/xpg6/bin/getconf -a

ksh93
getconf [-abdlpqrtw] [-c RE] [-n RE] [-s RE] [-v name][name [path [value]] ...]

DESCRIPTION

/usr/bin/getconf, /usr/xpg4/bin/getconf, /usr/xpg6/bin/getconf
In the first synopsis form, the getconf utility writes to the
standard output the value of the variable specified by system_var, in
accordance with specification if the -v option is used.

In the second synopsis form, getconf writes to the standard output
the value of the variable specified by path_var for the path
specified by pathname, in accordance with specification if the -v
option is used.

In the third synopsis form, config writes to the standard output the
names of the current system configuration variables.

The value of each configuration variable is determined as if it were
obtained by calling the function from which it is defined to be
available. The value reflects conditions in the current operating
environment.

ksh93
The getconf built-in in ksh93 is associated with the /bin and
/usr/bin paths. It is invoked when getconf is executed without a
pathname prefix and the pathname search finds a /bin/getconf or
/usr/bin/getconf executable.

getconf displays the system configuration value for name. If name is
a filesystem specific variable, the value is determined relative to
path, or, the current directory, if path is omitted. If value is
specified, getconf attempts to change the process local value to
value. - can be used in place of path when it is not relevant. Only
writable variables can be set. readonly variables cannot be changed.

The current value for name is written to the standard output. If name
is valid but undefined, undefined is written to the standard output.
If name is invalid or an error occurs in determining its value, a
diagnostic is written to standard error and getconf exits with a non-
zero exit status.

More than one variable can be set or queried by providing the name
path value 3-tuple for each variable, specifying - for value when
querying.

If no operands are specified, all known variables are written in
name=value form to the standard output, one per line. Only one of
--call, --name or --standard can be specified.

OPTIONS

/usr/bin/getconf, /usr/xpg4/bin/getconf, /usr/xpg6/bin/getconf
The following options are supported by /usr/bin/getconf,
/usr/xpg4/bin/getconf, and /usr/xpg6/bin/getconf

-a
Writes the names of the current system
configuration variables to the standard output.

-vspecification
Gives the specification which governs the
selection of values for configuration variables.

ksh93
The following options are supported by the getconf built-in command
in ksh93:

-a
--all
Call the native getconf -a.

-b
--base
List base variable name without call and
standard prefixes.

-c
--call=RE
Display variables with call prefix that
matches RE. The call prefixes are:

o CS

confstr(3C),

o PC

pathconf(2)

o SC

sysconf(3C)

o SI

sysinfo(2)

o XX

Constant value

-d
--defined
Only display defined values when no operands
are specified.

-l
--lowercase
List variable names in lower case.

-n
--name=RE
Display variables with names that match RE.

-p
--portable
Display the named writable variables and
values in a form that can be directly
executed by ksh93(1) to set the values. If
name is omitted, lists all writable
variables.

-q
--quote
Quote values ("...").

-r
--readonly
Display the named readonly variables in
name=value form. If name is omitted, lists
all readonly variables.

-s
--standard=RE
Display variables with standard prefix that
matches RE. Use the --table option to view
all standard prefixes, including local
additions.

The standard prefixes available on all
systems are:

AES
AST
C
GNU
POSIX
SVID
XBS5
XOPEN
XPG

-t
--table
Display the internal table that contains the
name, standard, standard section, and system
call symbol prefix for each variable.

-w
--writable
Display the named writable variables in
name=value form. If name is omitted, lists
all writable variables.

-v
--specification=name
Call the native getconf -v name.

OPERANDS

/usr/bin/getconf, /usr/xpg4/bin/getconf, /usr/xpg6/bin/getconf
The following operands are supported by /usr/bin/getconf,
/usr/xpg4/bin/getconf, and /usr/xpg6/bin/getconf:

path_var
A name of a configuration variable whose value is
available from the pathconf(2) function. All of the
values in the following table are supported:

ACL_ENABLED NAME_MAX XATTR_ENABLED
LINK_MAX PATH_MAX XATTR_EXISTS
MAX_CANON PIPE_BUF _POSIX_CHOWN_RESTRICTED
MAX_INPUT SATTR_ENABLED _POSIX_NO_TRUNC
MIN_HOLE_SIZE SATTR_EXISTS _POSIX_VDISABLE

pathname
A path name for which the variable specified by
path_var is to be determined.

system_var
A name of a configuration variable whose value is
available from confstr(3C) or sysconf(3C). All of the
values in the following table are supported:

ARG_MAX BC_BASE_MAX
BC_DIM_MAX BC_SCALE_MAX
BC_STRING_MAX CHAR_BIT
CHARCLASS_NAME_MAX CHAR_MAX
CHAR_MIN CHILD_MAX
CLK_TCK COLL_WEIGHTS_MAX
CS_PATH EXPR_NEST_MAX
HOST_NAME_MAX INT_MAX
INT_MIN LFS64_CFLAGS
LFS64_LDFLAGS LFS64_LIBS
LFS64_LINTFLAGS LFS_CFLAGS
LFS_LDFLAGS LFS_LIBS
LFS_LINTFLAGS LINE_MAX
LONG_BIT LONG_MAX
LONG_MIN MB_LEN_MAX
NGROUPS_MAX NL_ARGMAX
NL_LANGMAX NL_MSGMAX
NL_NMAX NL_SETMAX
NL_TEXTMAX NPROCESSORS_CONF
NPROCESSORS_MAX NPROCESSORS_ONLN
NZERO OPEN_MAX
POSIX2_BC_BASE_MAX POSIX2_BC_DIM_MAX
POSIX2_BC_SCALE_MAX POSIX2_BC_STRING_MAX
POSIX2_C_BIND POSIX2_C_DEV
POSIX2_CHAR_TERM POSIX2_COLL_WEIGHTS_MAX
POSIX2_C_VERSION POSIX2_EXPR_NEST_MAX
POSIX2_FORT_DEV POSIX2_FORT_RUN
POSIX2_LINE_MAX POSIX2_LOCALEDEF
POSIX2_RE_DUP_MAX POSIX2_SW_DEV
POSIX2_SYMLINKS POSIX2_UPE
POSIX2_VERSION POSIX_ALLOC_SIZE_MIN
POSIX_REC_INCR_XFER_SIZE POSIX_REC_MAX_XFER_SIZE
POSIX_REC_MIN_XFER_SIZE POSIX_REC_XFER_ALIGN
POSIX_V6_ILP32_OFF32 POSIX_V6_ILP32_OFF32_CFLAGS
POSIX_V6_ILP32_OFF32_LDFLAGS POSIX_V6_ILP32_OFF32_LIBS
POSIX_V6_ILP32_OFFBIG POSIX_V6_ILP32_OFFBIG_CFLAGS
POSIX_V6_ILP32_OFFBIG_LDFLAGS POSIX_V6_ILP32_OFFBIG_LIBS
POSIX_V6_LP64_OFF64 POSIX_V6_LP64_OFF64_CFLAGS
POSIX_V6_LP64_OFF64_LDFLAGS POSIX_V6_LP64_OFF64_LIBS
POSIX_V6_LPBIG_OFFBIG POSIX_V6_LPBIG_OFFBIG_CFLAGS
POSIX_V6_LPBIG_OFFBIG_LDFLAGS POSIX_V6_LPBIG_OFFBIG_LIBS
POSIX_V6_WIDTH_RESTRICTED_ENVS SYMLINK_MAX
SYMLOOP_MAX _POSIX2_BC_BASE_MAX
_POSIX2_BC_DIM_MAX _POSIX2_BC_SCALE_MAX
_POSIX2_BC_STRING_MAX _POSIX2_CHARCLASS_NAME_MAX
_POSIX2_CHAR_TERM _POSIX2_COLL_WEIGHTS_MAX
_POSIX2_C_BIND _POSIX2_C_DEV
_POSIX2_C_VERSION _POSIX2_EXPR_NEST_MAX
_POSIX2_FORT_DEV _POSIX2_FORT_RUN
_POSIX2_LINE_MAX _POSIX2_LOCALEDEF
_POSIX2_PBS _POSIX2_PBS_ACCOUNTING
_POSIX2_PBS_CHECKPOINT _POSIX2_PBS_LOCATE
_POSIX2_PBS_MESSAGE _POSIX2_PBS_TRACK
_POSIX2_RE_DUP_MAX _POSIX2_SW_DEV
_POSIX2_UPE _POSIX2_VERSION
_POSIX_ADVISORY_INFO _POSIX_AIO_LISTIO_MAX
_POSIX_AIO_MAX _POSIX_ARG_MAX
_POSIX_ASYNC_IO _POSIX_BARRIERS
_POSIX_CHILD_MAX _POSIX_CLOCKRES_MIN
_POSIX_CLOCK_SELECTION _POSIX_CPUTIME
_POSIX_DELAYTIMER_MAX _POSIX_HOST_NAME_MAX
_POSIX_IPV6 _POSIX_JOB_CONTROL
_POSIX_LINK_MAX _POSIX_LOGIN_NAME_MAX
_POSIX_MAX_CANON _POSIX_MAX_INPUT
_POSIX_MONOTONIC_CLOCK _POSIX_MQ_OPEN_MAX
_POSIX_MQ_PRIO_MAX _POSIX_NAME_MAX
_POSIX_NGROUPS_MAX _POSIX_OPEN_MAX
_POSIX_PATH_MAX _POSIX_PIPE_BUF
_POSIX_PRIO_IO _POSIX_RAW_SOCKETS
_POSIX_READER_WRITER_LOCKS _POSIX_REGEXP
_POSIX_RE_DUP_MAX _POSIX_RTSIG_MAX
_POSIX_SAVED_IDS _POSIX_SEM_NSEMS_MAX
_POSIX_SEM_VALUE_MAX _POSIX_SHELL
_POSIX_SIGQUEUE_MAX _POSIX_SPAWN
_POSIX_SPIN_LOCKS _POSIX_SPORADIC_SERVER
_POSIX_SSIZE_MAX _POSIX_SS_REPL_MAX
_POSIX_STREAM_MAX _POSIX_SYMLINK_MAX
_POSIX_SYMLOOP_MAX _POSIX_SYNC_IO
_POSIX_THREAD_ATTR_STACKADDR _POSIX_THREAD_ATTR_STACKSIZE
_POSIX_THREAD_CPUTIME _POSIX_THREAD_DESTRUCTOR_ITERATIONS
_POSIX_THREAD_KEYS_MAX _POSIX_THREAD_PRIORITY_SCHEDULING
_POSIX_THREAD_PRIO_INHERIT _POSIX_THREAD_PRIO_PROTECT
_POSIX_THREAD_PROCESS_SHARED _POSIX_THREAD_SAFE_FUNCTIONS
_POSIX_THREAD_SPORADIC_SERVER _POSIX_THREAD_THREADS_MAX
_POSIX_TIMEOUTS _POSIX_TIMER_MAX
_POSIX_TRA_POSIX_TIMER_MAXCE _POSIX_TIMESTAMP_RESOLUTION
_POSIX_TRACE_EVENT_FILTER _POSIX_TRACE_EVENT_NAME_MAX
_POSIX_TRACE_INHERIT _POSIX_TRACE_LOG
_POSIX_TRACE_NAME_MAX _POSIX_TRACE_SYS_MAX
_POSIX_TRACE_USER_EVENT_MAX _POSIX_TTY_NAME_MAX
_POSIX_TYPED_MEMORY_OBJECTS _POSIX_TZNAME_MAX
_POSIX_VERSION _POSIX_V6_ILP32_OFF32
_POSIX_V6_ILP32_OFFBIG _POSIX_V6_LP64_OFF64
_POSIX_V6_LPBIG_OFFBIG _V6_ILP32_OFF32
_V6_ILP32_OFFBIG _V6_LP64_OFF64
_V6_LPBIG_OFFBIG RE_DUP_MAX
SCHAR_MAX SCHAR_MIN
SHRT_MAX SHRT_MIN
SSIZE_MAX STREAM_MAX
TMP_MAX TZNAME_MAX
UCHAR_MAX UINT_MAX
ULONG_MAX USHRT_MAX
WORD_BIT XBS5_ILP32_OFF32
XBS5_ILP32_OFF32_CFLAGS XBS5_ILP32_OFF32_LDFLAGS
XBS5_ILP32_OFF32_LIBS XBS5_ILP32_OFF32_LINTFLAGS
XBS5_ILP32_OFFBIG XBS5_ILP32_OFFBIG_CFLAGS
XBS5_ILP32_OFFBIG_LDFLAGS XBS5_ILP32_OFFBIG_LIBS
XBS5_ILP32_OFFBIG_LINTFLAGS XBS5_LP64_OFF64
XBS5_LP64_OFF64_CFLAGS XBS5_LP64_OFF64_LDFLAGS
XBS5_LP64_OFF64_LIBS XBS5_LP64_OFF64_LINTFLAGS
XBS5_LPBIG_OFFBIG XBS5_LPBIG_OFFBIG_CFLAGS
XBS5_LPBIG_OFFBIG_LDFLAGS XBS5_LPBIG_OFFBIG_LIBS
XBS5_LPBIG_OFFBIG_LINTFLAGS _XOPEN_CRYPT
_XOPEN_ENH_I18N _XOPEN_IOV_MAX
_XOPEN_LEGACY _XOPEN_NAME_MAX
_XOPEN_PATH_MAX _XOPEN_SHM
_XOPEN_STREAMS _XOPEN_VERSION
_XOPEN_XCU_VERSION _XOPEN_XPG2
_XOPEN_XPG3 _XOPEN_XPG4

The symbol PATH also is recognized, yielding the same value as the
confstr() name value CS_PATH.

USAGE

See largefile(7) for the description of the behavior of
/usr/bin/getconf when encountering files greater than or equal to 2
Gbyte ( 2^31 bytes).

EXAMPLES

Example 1: Writing the Value of a Variable

This example illustrates the value of {NGROUPS_MAX}:

example% getconf NGROUPS_MAX

Example 2: Writing the Value of a Variable for a Specific Directory

This example illustrates the value of NAME_MAX for a specific
directory:

example% getconf NAME_MAX /usr

Example 3: Dealing with Unspecified Results

This example shows how to deal more carefully with results that might
be unspecified:

if value=$(getconf PATH_MAX /usr); then
if [ "$value" = "undefined" ]; then
echo PATH_MAX in /usr is infinite.
else
echo PATH_MAX in /usr is $value.
fi
else
echo Error in getconf.
fi

For example:

sysconf(_SC_POSIX_C_BIND);

and

system("getconf POSIX2_C_BIND");

in a C program could give different answers. The sysconf call
supplies a value that corresponds to the conditions when the program
was either compiled or executed, depending on the implementation. The
system call to getconf always supplies a value corresponding to
conditions when the program is executed.

ENVIRONMENT VARIABLES

See environ(7) for descriptions of the following environment
variables that affect the execution of getconf: LANG, LC_ALL,
LC_CTYPE, LC_MESSAGES, and NLSPATH.

The following environment variable is supported by the ksh93 built-in
getconf command:

_AST_FEATURES
Local writable values that are different from the
default are stored in the _AST_FEATURES environment
variable. The _AST_FEATURES value is a space-
separated list of name path value 3-tuples, where
name is the system configuration name, path is the
corresponding path, - if no path is applicable, and
value is the system configuration value.

EXIT STATUS

The following exit values are returned:

0
The specified variable is valid and information about its
current state was written successfully.

>0
An error occurred.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

/usr/bin/getconf, /usr/xpg4/bin/getconf, /usr/xpg6/bin/getconf

+--------------------+-------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------+
|Interface Stability | Committed |
+--------------------+-------------------+
|Standard | See standards(7). |
+--------------------+-------------------+

ksh93

+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | See below. |
+--------------------+-----------------+

The ksh93 built-in binding to /bin and /usr/bin is Volatile. The
built-in command-line interface is Committed.