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Table of contents- OS
- OS constants
- Error constants
- OS constants
OS#
Paper ply mac os. Source Code:lib/os.js
The os
module provides operating system-related utility methods andproperties. It can be accessed using:
os.EOL
#
The operating system-specific end-of-line marker.
n
on POSIXrn
on Windows
os.arch()
#
- Returns:
Returns the operating system CPU architecture for which the Node.js binary wascompiled. Possible values are 'arm'
, 'arm64'
, 'ia32'
, 'mips'
,'mipsel'
, 'ppc'
, 'ppc64'
, 's390'
, 's390x'
, 'x32'
, and 'x64'
.
The return value is equivalent to process.arch
. Proceeding back mac os.
os.constants
#
Contains commonly used operating system-specific constants for error codes,process signals, and so on. The specific constants defined are described inOS constants.
os.cpus()
#
- Returns:
Wavebook mac os. Returns an array of objects containing information about each logical CPU core.
The properties included on each object include: Qwars mac os.
model
speed
(in MHz)times
user
The number of milliseconds the CPU has spent in user mode.nice
The number of milliseconds the CPU has spent in nice mode.sys
The number of milliseconds the CPU has spent in sys mode.idle
The number of milliseconds the CPU has spent in idle mode.irq
The number of milliseconds the CPU has spent in irq mode.
nice
values are POSIX-only. On Windows, thenice
values of all processorsare always 0.os.endianness()
#- Returns:
Returns a string identifying the endianness of the CPU for which the Node.jsbinary was compiled.
Possible values are
'BE'
for big endian and'LE'
for little endian.os.freemem()
#- Returns:
Returns the amount of free system memory in bytes as an integer.
os.getPriority([pid])
#pid
The process ID to retrieve scheduling priority for.Default:0
.- Returns:
Returns the scheduling priority for the process specified by
pid
. Ifpid
isnot provided or is0
, the priority of the current process is returned.os.homedir()
#- Returns:
Returns the string path of the current user's home directory.
Slash Sequence Mac Os Download
On POSIX, it uses the
$HOME
environment variable if defined. Otherwise ituses the effective UID to look up the user's home directory.Slash Sequence Mac Os 11
On Windows, it uses the
USERPROFILE
environment variable if defined.Otherwise it uses the path to the profile directory of the current user.os.hostname()
#- Returns:
Turtle simulator: aquatic edition mac os. F3s (beta) *paused because im not ready! mac os. Returns the host name of the operating system as a string.
os.loadavg()
#- Returns:
Returns an array containing the 1, 5, and 15 minute load averages.
The load average is a measure of system activity calculated by the operatingsystem and expressed as a fractional number. Stuck in a groove mac os.
The load average is a Unix-specific concept. On Windows, the return value isalways
[0, 0, 0]
.os.networkInterfaces()
#- Returns:
Returns an object containing network interfaces that have been assigned anetwork address.
Each key on the returned object identifies a network interface. The associatedvalue is an array of objects that each describe an assigned network address.
The properties available on the assigned network address object include:
address
The assigned IPv4 or IPv6 addressnetmask
The IPv4 or IPv6 network maskfamily
EitherIPv4
orIPv6
mac
The MAC address of the network interfaceinternal
true
if the network interface is a loopback orsimilar interface that is not remotely accessible; otherwisefalse
scopeid
The numeric IPv6 scope ID (only specified whenfamily
isIPv6
)cidr
The assigned IPv4 or IPv6 address with the routing prefixin CIDR notation. If thenetmask
is invalid, this property is settonull
.
os.platform()
#- Returns:
Returns a string identifying the operating system platform. The value is setat compile time. Possible values are
'aix'
,'darwin'
,'freebsd'
,'linux'
,'openbsd'
,'sunos'
, and'win32'
.The return value is equivalent to
process.platform
.The value
'android'
may also be returned if Node.js is built on the Androidoperating system. Android support is experimental.os.release()
#- Returns:
Returns the operating system as a string.
On POSIX systems, the operating system release is determined by calling
uname(3)
. On Windows,GetVersionExW()
is used. Seehttps://en.wikipedia.org/wiki/Uname#Examples for more information.os.setPriority([pid, ]priority)
#pid
The process ID to set scheduling priority for.Default:0
.priority
The scheduling priority to assign to the process.
Attempts to set the scheduling priority for the process specified by
pid
. Ifpid
is not provided or is0
, the process ID of the current process is used.The
priority
input must be an integer between-20
(high priority) and19
(low priority). Due to differences between Unix priority levels and Windowspriority classes,priority
is mapped to one of six priority constants inos.constants.priority
. When retrieving a process priority level, this rangemapping may cause the return value to be slightly different on Windows. To avoidconfusion, setpriority
to one of the priority constants.On Windows, setting priority to
PRIORITY_HIGHEST
requires elevated userprivileges. Otherwise the set priority will be silently reduced toPRIORITY_HIGH
.os.tmpdir()
#- Returns:
Returns the operating system's default directory for temporary files as astring.
os.totalmem()
#- Returns:
Returns the total amount of system memory in bytes as an integer.
os.type()
#- Returns:
Returns the operating system name as returned by uname(3)
. For example, itreturns 'Linux'
on Linux, 'Darwin'
on macOS, and 'Windows_NT'
on Windows.
See https://en.wikipedia.org/wiki/Uname#Examples for additional informationabout the output of running uname(3)
on various operating systems.
os.uptime()
#
- Returns:
Returns the system uptime in number of seconds.
The value returned can be inaccurate in somerare virtualization cases. The issue arises when the virtualizedguest instance shares the kernel with the host system.Due to the fact that libuv uses a syscall thatprovides host's uptime instead of guest'suptime on OpenVZ, os.uptime()
may also provideerroneous result.
Please refer to https://github.com/nodejs/node/issues/36244 andhttps://github.com/libuv/libuv/issues/3068 for an exploration ofthis issue, until it is resolved by libuv.
os.userInfo([options])
#
options
encoding
Character encoding used to interpret resulting strings.Ifencoding
is set to'buffer'
, theusername
,shell
, andhomedir
values will beBuffer
instances. Default:'utf8'
.
- Returns:
Returns information about the currently effective user. On POSIX platforms,this is typically a subset of the password file. The returned object includesthe
username
,uid
,gid
,shell
, andhomedir
. On Windows, theuid
andgid
fields are-1
, andshell
isnull
.The value of
homedir
returned byos.userInfo()
is provided by the operatingsystem. This differs from the result ofos.homedir()
, which queriesenvironment variables for the home directory before falling back to theoperating system response.Throws a
SystemError
if a user has nousername
orhomedir
.os.version()
#- Returns
Returns a string identifying the kernel version.
On POSIX systems, the operating system release is determined by calling
uname(3)
. On Windows,RtlGetVersion()
is used, and if it is notavailable,GetVersionExW()
will be used. Seehttps://en.wikipedia.org/wiki/Uname#Examples for more information.OS constants#
The following constants are exported by
os.constants
.Not all constants will be available on every operating system.
Signal constants#
The following signal constants are exported by
os.constants.signals
.
Returns the operating system name as returned by uname(3)
. For example, itreturns 'Linux'
on Linux, 'Darwin'
on macOS, and 'Windows_NT'
on Windows.
See https://en.wikipedia.org/wiki/Uname#Examples for additional informationabout the output of running uname(3)
on various operating systems.
os.uptime()
#
- Returns:
Returns the system uptime in number of seconds.
The value returned can be inaccurate in somerare virtualization cases. The issue arises when the virtualizedguest instance shares the kernel with the host system.Due to the fact that libuv uses a syscall thatprovides host's uptime instead of guest'suptime on OpenVZ, os.uptime()
may also provideerroneous result.
Please refer to https://github.com/nodejs/node/issues/36244 andhttps://github.com/libuv/libuv/issues/3068 for an exploration ofthis issue, until it is resolved by libuv.
os.userInfo([options])
#
options
encoding
Character encoding used to interpret resulting strings.Ifencoding
is set to'buffer'
, theusername
,shell
, andhomedir
values will beBuffer
instances. Default:'utf8'
.
- Returns:
Returns information about the currently effective user. On POSIX platforms,this is typically a subset of the password file. The returned object includesthe
username
,uid
,gid
,shell
, andhomedir
. On Windows, theuid
andgid
fields are-1
, andshell
isnull
.The value of
homedir
returned byos.userInfo()
is provided by the operatingsystem. This differs from the result ofos.homedir()
, which queriesenvironment variables for the home directory before falling back to theoperating system response.Throws a
SystemError
if a user has nousername
orhomedir
.os.version()
#- Returns
Returns a string identifying the kernel version.
On POSIX systems, the operating system release is determined by calling
uname(3)
. On Windows,RtlGetVersion()
is used, and if it is notavailable,GetVersionExW()
will be used. Seehttps://en.wikipedia.org/wiki/Uname#Examples for more information.OS constants#
The following constants are exported by
os.constants
.Not all constants will be available on every operating system.
Signal constants#
The following signal constants are exported by
os.constants.signals
.Constant Description SIGHUP
Sent to indicate when a controlling terminal is closed or a parent process exits. SIGINT
Sent to indicate when a user wishes to interrupt a process (Ctrl+C). SIGQUIT
Sent to indicate when a user wishes to terminate a process and perform a core dump. SIGILL
Sent to a process to notify that it has attempted to perform an illegal, malformed, unknown, or privileged instruction. SIGTRAP
Sent to a process when an exception has occurred. SIGABRT
Sent to a process to request that it abort. SIGIOT
Synonym for SIGABRT
SIGBUS
Sent to a process to notify that it has caused a bus error. SIGFPE
Sent to a process to notify that it has performed an illegal arithmetic operation. SIGKILL
Sent to a process to terminate it immediately. SIGUSR1
SIGUSR2
Sent to a process to identify user-defined conditions. SIGSEGV
Sent to a process to notify of a segmentation fault. SIGPIPE
Sent to a process when it has attempted to write to a disconnected pipe. SIGALRM
Sent to a process when a system timer elapses. SIGTERM
Sent to a process to request termination. SIGCHLD
Sent to a process when a child process terminates. SIGSTKFLT
Sent to a process to indicate a stack fault on a coprocessor. SIGCONT
Sent to instruct the operating system to continue a paused process. SIGSTOP
Sent to instruct the operating system to halt a process. SIGTSTP
Sent to a process to request it to stop. SIGBREAK
Sent to indicate when a user wishes to interrupt a process. SIGTTIN
Sent to a process when it reads from the TTY while in the background. SIGTTOU
Sent to a process when it writes to the TTY while in the background. SIGURG
Sent to a process when a socket has urgent data to read. SIGXCPU
Sent to a process when it has exceeded its limit on CPU usage. SIGXFSZ
Sent to a process when it grows a file larger than the maximum allowed. SIGVTALRM
Sent to a process when a virtual timer has elapsed. SIGPROF
Sent to a process when a system timer has elapsed. SIGWINCH
Sent to a process when the controlling terminal has changed its size. SIGIO
Sent to a process when I/O is available. SIGPOLL
Synonym for SIGIO
SIGLOST
Sent to a process when a file lock has been lost. SIGPWR
Sent to a process to notify of a power failure. SIGINFO
Synonym for SIGPWR
SIGSYS
Sent to a process to notify of a bad argument. SIGUNUSED
Synonym for SIGSYS
Error constants#
The following error constants are exported by
os.constants.errno
.POSIX error constants#
Constant Description E2BIG
Indicates that the list of arguments is longer than expected. EACCES
Indicates that the operation did not have sufficient permissions. EADDRINUSE
Indicates that the network address is already in use. EADDRNOTAVAIL
Indicates that the network address is currently unavailable for use. EAFNOSUPPORT
Indicates that the network address family is not supported. EAGAIN
Indicates that there is no data available and to try the operation again later. EALREADY
Indicates that the socket already has a pending connection in progress. EBADF
Indicates that a file descriptor is not valid. EBADMSG
Indicates an invalid data message. EBUSY
Indicates that a device or resource is busy. ECANCELED
Indicates that an operation was canceled. ECHILD
Indicates that there are no child processes. ECONNABORTED
Indicates that the network connection has been aborted. ECONNREFUSED
Indicates that the network connection has been refused. ECONNRESET
Indicates that the network connection has been reset. EDEADLK
Indicates that a resource deadlock has been avoided. EDESTADDRREQ
Indicates that a destination address is required. EDOM
Indicates that an argument is out of the domain of the function. EDQUOT
Indicates that the disk quota has been exceeded. EEXIST
Indicates that the file already exists. EFAULT
Indicates an invalid pointer address. EFBIG
Indicates that the file is too large. EHOSTUNREACH
Indicates that the host is unreachable. EIDRM
Indicates that the identifier has been removed. EILSEQ
Indicates an illegal byte sequence. EINPROGRESS
Indicates that an operation is already in progress. EINTR
Indicates that a function call was interrupted. EINVAL
Indicates that an invalid argument was provided. EIO
Indicates an otherwise unspecified I/O error. EISCONN
Indicates that the socket is connected. EISDIR
Indicates that the path is a directory. ELOOP
Indicates too many levels of symbolic links in a path. EMFILE
Indicates that there are too many open files. EMLINK
Indicates that there are too many hard links to a file. EMSGSIZE
Indicates that the provided message is too long. EMULTIHOP
Indicates that a multihop was attempted. ENAMETOOLONG
Indicates that the filename is too long. ENETDOWN
Indicates that the network is down. ENETRESET
Indicates that the connection has been aborted by the network. ENETUNREACH
Indicates that the network is unreachable. ENFILE
Indicates too many open files in the system. ENOBUFS
Indicates that no buffer space is available. ENODATA
Indicates that no message is available on the stream head read queue. ENODEV
Indicates that there is no such device. ENOENT
Indicates that there is no such file or directory. ENOEXEC
Indicates an exec format error. ENOLCK
Indicates that there are no locks available. ENOLINK
Indications that a link has been severed. ENOMEM
Indicates that there is not enough space. ENOMSG
Indicates that there is no message of the desired type. ENOPROTOOPT
Indicates that a given protocol is not available. ENOSPC
Indicates that there is no space available on the device. ENOSR
Indicates that there are no stream resources available. ENOSTR
Indicates that a given resource is not a stream. ENOSYS
Indicates that a function has not been implemented. ENOTCONN
Indicates that the socket is not connected. ENOTDIR
Indicates that the path is not a directory. ENOTEMPTY
Indicates that the directory is not empty. ENOTSOCK
Indicates that the given item is not a socket. ENOTSUP
Indicates that a given operation is not supported. ENOTTY
Indicates an inappropriate I/O control operation. ENXIO
Indicates no such device or address. EOPNOTSUPP
Indicates that an operation is not supported on the socket. Although ENOTSUP
andEOPNOTSUPP
have the same value on Linux, according to POSIX.1 these error values should be distinct.)EOVERFLOW
Indicates that a value is too large to be stored in a given data type. EPERM
Indicates that the operation is not permitted. EPIPE
Indicates a broken pipe. EPROTO
Indicates a protocol error. EPROTONOSUPPORT
Indicates that a protocol is not supported. EPROTOTYPE
Indicates the wrong type of protocol for a socket. ERANGE
Indicates that the results are too large. EROFS
Indicates that the file system is read only. ESPIPE
Indicates an invalid seek operation. ESRCH
Indicates that there is no such process. ESTALE
Indicates that the file handle is stale. ETIME
Indicates an expired timer. ETIMEDOUT
Indicates that the connection timed out. ETXTBSY
Indicates that a text file is busy. EWOULDBLOCK
Indicates that the operation would block. EXDEV
Indicates an improper link. Windows-specific error constants#
The following error codes are specific to the Windows operating system.
Constant Description WSAEINTR
Indicates an interrupted function call. WSAEBADF
Indicates an invalid file handle. WSAEACCES
Indicates insufficient permissions to complete the operation. WSAEFAULT
Indicates an invalid pointer address. WSAEINVAL
Indicates that an invalid argument was passed. WSAEMFILE
Indicates that there are too many open files. WSAEWOULDBLOCK
Indicates that a resource is temporarily unavailable. WSAEINPROGRESS
Indicates that an operation is currently in progress. WSAEALREADY
Indicates that an operation is already in progress. WSAENOTSOCK
Indicates that the resource is not a socket. WSAEDESTADDRREQ
Indicates that a destination address is required. WSAEMSGSIZE
Indicates that the message size is too long. WSAEPROTOTYPE
Indicates the wrong protocol type for the socket. WSAENOPROTOOPT
Indicates a bad protocol option. WSAEPROTONOSUPPORT
Indicates that the protocol is not supported. WSAESOCKTNOSUPPORT
Indicates that the socket type is not supported. WSAEOPNOTSUPP
Indicates that the operation is not supported. WSAEPFNOSUPPORT
Indicates that the protocol family is not supported. WSAEAFNOSUPPORT
Indicates that the address family is not supported. WSAEADDRINUSE
Indicates that the network address is already in use. WSAEADDRNOTAVAIL
Indicates that the network address is not available. WSAENETDOWN
Indicates that the network is down. WSAENETUNREACH
Indicates that the network is unreachable. WSAENETRESET
Indicates that the network connection has been reset. WSAECONNABORTED
Indicates that the connection has been aborted. WSAECONNRESET
Indicates that the connection has been reset by the peer. WSAENOBUFS
Indicates that there is no buffer space available. WSAEISCONN
Indicates that the socket is already connected. WSAENOTCONN
Indicates that the socket is not connected. WSAESHUTDOWN
Indicates that data cannot be sent after the socket has been shutdown. WSAETOOMANYREFS
Indicates that there are too many references. WSAETIMEDOUT
Indicates that the connection has timed out. WSAECONNREFUSED
Indicates that the connection has been refused. WSAELOOP
Indicates that a name cannot be translated. WSAENAMETOOLONG
Indicates that a name was too long. WSAEHOSTDOWN
Indicates that a network host is down. WSAEHOSTUNREACH
Indicates that there is no route to a network host. WSAENOTEMPTY
Indicates that the directory is not empty. WSAEPROCLIM
Indicates that there are too many processes. WSAEUSERS
Indicates that the user quota has been exceeded. WSAEDQUOT
Indicates that the disk quota has been exceeded. WSAESTALE
Indicates a stale file handle reference. WSAEREMOTE
Indicates that the item is remote. WSASYSNOTREADY
Indicates that the network subsystem is not ready. WSAVERNOTSUPPORTED
Indicates that the winsock.dll
version is out of range.WSANOTINITIALISED
Indicates that successful WSAStartup has not yet been performed. WSAEDISCON
Indicates that a graceful shutdown is in progress. WSAENOMORE
Indicates that there are no more results. WSAECANCELLED
Indicates that an operation has been canceled. WSAEINVALIDPROCTABLE
Indicates that the procedure call table is invalid. WSAEINVALIDPROVIDER
Indicates an invalid service provider. WSAEPROVIDERFAILEDINIT
Indicates that the service provider failed to initialized. WSASYSCALLFAILURE
Indicates a system call failure. WSASERVICE_NOT_FOUND
Indicates that a service was not found. WSATYPE_NOT_FOUND
Indicates that a class type was not found. WSA_E_NO_MORE
Indicates that there are no more results. WSA_E_CANCELLED
Indicates that the call was canceled. WSAEREFUSED
Indicates that a database query was refused. dlopen constants#
If available on the operating system, the following constantsare exported in
os.constants.dlopen
. Seedlopen(3)
for detailedinformation.Constant Description RTLD_LAZY
Perform lazy binding. Node.js sets this flag by default. RTLD_NOW
Resolve all undefined symbols in the library before dlopen(3) returns. RTLD_GLOBAL
Symbols defined by the library will be made available for symbol resolution of subsequently loaded libraries. RTLD_LOCAL
The converse of RTLD_GLOBAL
. This is the default behavior if neither flag is specified.RTLD_DEEPBIND
Make a self-contained library use its own symbols in preference to symbols from previously loaded libraries. Priority constants#
The following process scheduling constants are exported by
os.constants.priority
.Constant Description PRIORITY_LOW
The lowest process scheduling priority. This corresponds to IDLE_PRIORITY_CLASS
on Windows, and a nice value of19
on all other platforms.PRIORITY_BELOW_NORMAL
The process scheduling priority above PRIORITY_LOW
and belowPRIORITY_NORMAL
. This corresponds toBELOW_NORMAL_PRIORITY_CLASS
on Windows, and a nice value of10
on all other platforms.PRIORITY_NORMAL
The default process scheduling priority. This corresponds to NORMAL_PRIORITY_CLASS
on Windows, and a nice value of0
on all other platforms.PRIORITY_ABOVE_NORMAL
The process scheduling priority above PRIORITY_NORMAL
and belowPRIORITY_HIGH
. This corresponds toABOVE_NORMAL_PRIORITY_CLASS
on Windows, and a nice value of-7
on all other platforms.PRIORITY_HIGH
The process scheduling priority above PRIORITY_ABOVE_NORMAL
and belowPRIORITY_HIGHEST
. This corresponds toHIGH_PRIORITY_CLASS
on Windows, and a nice value of-14
on all other platforms.PRIORITY_HIGHEST
The highest process scheduling priority. This corresponds to REALTIME_PRIORITY_CLASS
on Windows, and a nice value of-20
on all other platforms.libuv constants#
Constant Description UV_UDP_REUSEADDR