Most visited

Recently visited

Added in API level 21

Os

public final class Os
extends Object

java.lang.Object
   ↳ android.system.Os


Access to low-level system functionality. Most of these are system calls. Most users will want to use higher-level APIs where available, but this class provides access to the underlying primitives used to implement the higher-level APIs.

The corresponding constants can be found in OsConstants.

Summary

Public methods

static FileDescriptor accept(FileDescriptor fd, InetSocketAddress peerAddress)

See accept(2).

static boolean access(String path, int mode)

See access(2).

static void bind(FileDescriptor fd, InetAddress address, int port)

See bind(2).

static void chmod(String path, int mode)

See chmod(2).

static void chown(String path, int uid, int gid)

See chown(2).

static void close(FileDescriptor fd)

See close(2).

static void connect(FileDescriptor fd, InetAddress address, int port)

See connect(2).

static FileDescriptor dup(FileDescriptor oldFd)

See dup(2).

static FileDescriptor dup2(FileDescriptor oldFd, int newFd)

See dup2(2).

static String[] environ()

See environ(3).

static void execv(String filename, String[] argv)

See execv(2).

static void execve(String filename, String[] argv, String[] envp)

See execve(2).

static void fchmod(FileDescriptor fd, int mode)

See fchmod(2).

static void fchown(FileDescriptor fd, int uid, int gid)

See fchown(2).

static void fdatasync(FileDescriptor fd)

See fdatasync(2).

static StructStat fstat(FileDescriptor fd)

See fstat(2).

static StructStatVfs fstatvfs(FileDescriptor fd)

See fstatvfs(2).

static void fsync(FileDescriptor fd)

See fsync(2).

static void ftruncate(FileDescriptor fd, long length)

See ftruncate(2).

static String gai_strerror(int error)

See gai_strerror(3).

static int getegid()

See getegid(2).

static String getenv(String name)

See getenv(3).

static int geteuid()

See geteuid(2).

static int getgid()

See getgid(2).

static SocketAddress getpeername(FileDescriptor fd)

See getpeername(2).

static int getpid()

See getpid(2).

static int getppid()

See getppid(2).

static SocketAddress getsockname(FileDescriptor fd)

See getsockname(2).

static int gettid()

See gettid(2).

static int getuid()

See getuid(2).

static String if_indextoname(int index)

See if_indextoname(3).

static InetAddress inet_pton(int family, String address)

See inet_pton(3).

static boolean isatty(FileDescriptor fd)

See isatty(3).

static void kill(int pid, int signal)

See kill(2).

static void lchown(String path, int uid, int gid)

See lchown(2).

static void link(String oldPath, String newPath)

See link(2).

static void listen(FileDescriptor fd, int backlog)

See listen(2).

static long lseek(FileDescriptor fd, long offset, int whence)

See lseek(2).

static StructStat lstat(String path)

See lstat(2).

static void mincore(long address, long byteCount, byte[] vector)

See mincore(2).

static void mkdir(String path, int mode)

See mkdir(2).

static void mkfifo(String path, int mode)

See mkfifo(3).

static void mlock(long address, long byteCount)

See mlock(2).

static long mmap(long address, long byteCount, int prot, int flags, FileDescriptor fd, long offset)

See mmap(2).

static void msync(long address, long byteCount, int flags)

See msync(2).

static void munlock(long address, long byteCount)

See munlock(2).

static void munmap(long address, long byteCount)

See munmap(2).

static FileDescriptor open(String path, int flags, int mode)

See open(2).

static FileDescriptor[] pipe()

See pipe(2).

static int poll(StructPollfd[] fds, int timeoutMs)

See poll(2).

static void posix_fallocate(FileDescriptor fd, long offset, long length)

See posix_fallocate(2).

static int prctl(int option, long arg2, long arg3, long arg4, long arg5)

See prctl(2).

static int pread(FileDescriptor fd, ByteBuffer buffer, long offset)

See pread(2).

static int pread(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, long offset)

See pread(2).

static int pwrite(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, long offset)

See pwrite(2).

static int pwrite(FileDescriptor fd, ByteBuffer buffer, long offset)

See pwrite(2).

static int read(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount)

See read(2).

static int read(FileDescriptor fd, ByteBuffer buffer)

See read(2).

static String readlink(String path)

See readlink(2).

static int readv(FileDescriptor fd, Object[] buffers, int[] offsets, int[] byteCounts)

See readv(2).

static int recvfrom(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, int flags, InetSocketAddress srcAddress)

See recvfrom(2).

static int recvfrom(FileDescriptor fd, ByteBuffer buffer, int flags, InetSocketAddress srcAddress)

See recvfrom(2).

static void remove(String path)

See remove(3).

static void rename(String oldPath, String newPath)

See rename(2).

static long sendfile(FileDescriptor outFd, FileDescriptor inFd, MutableLong inOffset, long byteCount)

See sendfile(2).

static int sendto(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount, int flags, InetAddress inetAddress, int port)

See sendto(2).

static int sendto(FileDescriptor fd, ByteBuffer buffer, int flags, InetAddress inetAddress, int port)

See sendto(2).

static void setegid(int egid)

See setegid(2).

static void setenv(String name, String value, boolean overwrite)

See setenv(3).

static void seteuid(int euid)

See seteuid(2).

static void setgid(int gid)

See setgid(2).

static int setsid()

See setsid(2).

static void setuid(int uid)

See setuid(2).

static void shutdown(FileDescriptor fd, int how)

See shutdown(2).

static FileDescriptor socket(int domain, int type, int protocol)

See socket(2).

static void socketpair(int domain, int type, int protocol, FileDescriptor fd1, FileDescriptor fd2)

See socketpair(2).

static StructStat stat(String path)

See stat(2).

static StructStatVfs statvfs(String path)

See statvfs(2).

static String strerror(int errno)

See strerror(2).

static String strsignal(int signal)

See strsignal(3).

static void symlink(String oldPath, String newPath)

See symlink(2).

static long sysconf(int name)

See sysconf(3).

static void tcdrain(FileDescriptor fd)

See tcdrain(3).

static void tcsendbreak(FileDescriptor fd, int duration)

See tcsendbreak(3).

static int umask(int mask)

See umask(2).

static StructUtsname uname()

See uname(2).

static void unsetenv(String name)

See unsetenv(3).

static int waitpid(int pid, MutableInt status, int options)

See waitpid(2).

static int write(FileDescriptor fd, ByteBuffer buffer)

See write(2).

static int write(FileDescriptor fd, byte[] bytes, int byteOffset, int byteCount)

See write(2).

static int writev(FileDescriptor fd, Object[] buffers, int[] offsets, int[] byteCounts)

See writev(2).

Inherited methods

From class java.lang.Object

Public methods

accept

Added in API level 21
FileDescriptor accept (FileDescriptor fd, 
                InetSocketAddress peerAddress)

See accept(2).

Parameters
fd FileDescriptor
peerAddress InetSocketAddress
Returns
FileDescriptor
Throws
ErrnoException
SocketException

access

Added in API level 21
boolean access (String path, 
                int mode)

See access(2).

Parameters
path String
mode int
Returns
boolean
Throws
ErrnoException

bind

Added in API level 21
void bind (FileDescriptor fd, 
                InetAddress address, 
                int port)

See bind(2).

Parameters
fd FileDescriptor
address InetAddress
port int
Throws
ErrnoException
SocketException

chmod

Added in API level 21
void chmod (String path, 
                int mode)

See chmod(2).

Parameters
path String
mode int
Throws
ErrnoException

chown

Added in API level 21
void chown (String path, 
                int uid, 
                int gid)

See chown(2).

Parameters
path String
uid int
gid int
Throws
ErrnoException

close

Added in API level 21
void close (FileDescriptor fd)

See close(2).

Parameters
fd FileDescriptor
Throws
ErrnoException

connect

Added in API level 21
void connect (FileDescriptor fd, 
                InetAddress address, 
                int port)

See connect(2).

Parameters
fd FileDescriptor
address InetAddress
port int
Throws
ErrnoException
SocketException

dup

Added in API level 21
FileDescriptor dup (FileDescriptor oldFd)

See dup(2).

Parameters
oldFd FileDescriptor
Returns
FileDescriptor
Throws
ErrnoException

dup2

Added in API level 21
FileDescriptor dup2 (FileDescriptor oldFd, 
                int newFd)

See dup2(2).

Parameters
oldFd FileDescriptor
newFd int
Returns
FileDescriptor
Throws
ErrnoException

environ

Added in API level 21
String[] environ ()

See environ(3).

Returns
String[]

execv

Added in API level 21
void execv (String filename, 
                String[] argv)

See execv(2).

Parameters
filename String
argv String
Throws
ErrnoException

execve

Added in API level 21
void execve (String filename, 
                String[] argv, 
                String[] envp)

See execve(2).

Parameters
filename String
argv String
envp String
Throws
ErrnoException

fchmod

Added in API level 21
void fchmod (FileDescriptor fd, 
                int mode)

See fchmod(2).

Parameters
fd FileDescriptor
mode int
Throws
ErrnoException

fchown

Added in API level 21
void fchown (FileDescriptor fd, 
                int uid, 
                int gid)

See fchown(2).

Parameters
fd FileDescriptor
uid int
gid int
Throws
ErrnoException

fdatasync

Added in API level 21
void fdatasync (FileDescriptor fd)

See fdatasync(2).

Parameters
fd FileDescriptor
Throws
ErrnoException

fstat

Added in API level 21
StructStat fstat (FileDescriptor fd)

See fstat(2).

Parameters
fd FileDescriptor
Returns
StructStat
Throws
ErrnoException

fstatvfs

Added in API level 21
StructStatVfs fstatvfs (FileDescriptor fd)

See fstatvfs(2).

Parameters
fd FileDescriptor
Returns
StructStatVfs
Throws
ErrnoException

fsync

Added in API level 21
void fsync (FileDescriptor fd)

See fsync(2).

Parameters
fd FileDescriptor
Throws
ErrnoException

ftruncate

Added in API level 21
void ftruncate (FileDescriptor fd, 
                long length)

See ftruncate(2).

Parameters
fd FileDescriptor
length long
Throws
ErrnoException

gai_strerror

Added in API level 21
String gai_strerror (int error)

See gai_strerror(3).

Parameters
error int
Returns
String

getegid

Added in API level 21
int getegid ()

See getegid(2).

Returns
int

getenv

Added in API level 21
String getenv (String name)

See getenv(3).

Parameters
name String
Returns
String

geteuid

Added in API level 21
int geteuid ()

See geteuid(2).

Returns
int

getgid

Added in API level 21
int getgid ()

See getgid(2).

Returns
int

getpeername

Added in API level 21
SocketAddress getpeername (FileDescriptor fd)

See getpeername(2).

Parameters
fd FileDescriptor
Returns
SocketAddress
Throws
ErrnoException

getpid

Added in API level 21
int getpid ()

See getpid(2).

Returns
int

getppid

Added in API level 21
int getppid ()

See getppid(2).

Returns
int

getsockname

Added in API level 21
SocketAddress getsockname (FileDescriptor fd)

See getsockname(2).

Parameters
fd FileDescriptor
Returns
SocketAddress
Throws
ErrnoException

gettid

Added in API level 21
int gettid ()

See gettid(2).

Returns
int

getuid

Added in API level 21
int getuid ()

See getuid(2).

Returns
int

if_indextoname

Added in API level 21
String if_indextoname (int index)

See if_indextoname(3).

Parameters
index int
Returns
String

inet_pton

Added in API level 21
InetAddress inet_pton (int family, 
                String address)

See inet_pton(3).

Parameters
family int
address String
Returns
InetAddress

isatty

Added in API level 21
boolean isatty (FileDescriptor fd)

See isatty(3).

Parameters
fd FileDescriptor
Returns
boolean

kill

Added in API level 21
void kill (int pid, 
                int signal)

See kill(2).

Parameters
pid int
signal int
Throws
ErrnoException

lchown

Added in API level 21
void lchown (String path, 
                int uid, 
                int gid)

See lchown(2).

Parameters
path String
uid int
gid int
Throws
ErrnoException

link

Added in API level 21
void link (String oldPath, 
                String newPath)

See link(2).

Parameters
oldPath String
newPath String
Throws
ErrnoException

listen

Added in API level 21
void listen (FileDescriptor fd, 
                int backlog)

See listen(2).

Parameters
fd FileDescriptor
backlog int
Throws
ErrnoException

lseek

Added in API level 21
long lseek (FileDescriptor fd, 
                long offset, 
                int whence)

See lseek(2).

Parameters
fd FileDescriptor
offset long
whence int
Returns
long
Throws
ErrnoException

lstat

Added in API level 21
StructStat lstat (String path)

See lstat(2).

Parameters
path String
Returns
StructStat
Throws
ErrnoException

mincore

Added in API level 21
void mincore (long address, 
                long byteCount, 
                byte[] vector)

See mincore(2).

Parameters
address long
byteCount long
vector byte
Throws
ErrnoException

mkdir

Added in API level 21
void mkdir (String path, 
                int mode)

See mkdir(2).

Parameters
path String
mode int
Throws
ErrnoException

mkfifo

Added in API level 21
void mkfifo (String path, 
                int mode)

See mkfifo(3).

Parameters
path String
mode int
Throws
ErrnoException

mlock

Added in API level 21
void mlock (long address, 
                long byteCount)

See mlock(2).

Parameters
address long
byteCount long
Throws
ErrnoException

mmap

Added in API level 21
long mmap (long address, 
                long byteCount, 
                int prot, 
                int flags, 
                FileDescriptor fd, 
                long offset)

See mmap(2).

Parameters
address long
byteCount long
prot int
flags int
fd FileDescriptor
offset long
Returns
long
Throws
ErrnoException

msync

Added in API level 21
void msync (long address, 
                long byteCount, 
                int flags)

See msync(2).

Parameters
address long
byteCount long
flags int
Throws
ErrnoException

munlock

Added in API level 21
void munlock (long address, 
                long byteCount)

See munlock(2).

Parameters
address long
byteCount long
Throws
ErrnoException

munmap

Added in API level 21
void munmap (long address, 
                long byteCount)

See munmap(2).

Parameters
address long
byteCount long
Throws
ErrnoException

open

Added in API level 21
FileDescriptor open (String path, 
                int flags, 
                int mode)

See open(2).

Parameters
path String
flags int
mode int
Returns
FileDescriptor
Throws
ErrnoException

pipe

Added in API level 21
FileDescriptor[] pipe ()

See pipe(2).

Returns
FileDescriptor[]
Throws
ErrnoException

poll

Added in API level 21
int poll (StructPollfd[] fds, 
                int timeoutMs)

See poll(2).

Note that in Lollipop this could throw an ErrnoException with EINTR. In later releases, the implementation will automatically just restart the system call with an appropriately reduced timeout.

Parameters
fds StructPollfd
timeoutMs int
Returns
int
Throws
ErrnoException

posix_fallocate

Added in API level 21
void posix_fallocate (FileDescriptor fd, 
                long offset, 
                long length)

See posix_fallocate(2).

Parameters
fd FileDescriptor
offset long
length long
Throws
ErrnoException

prctl

Added in API level 21
int prctl (int option, 
                long arg2, 
                long arg3, 
                long arg4, 
                long arg5)

See prctl(2).

Parameters
option int
arg2 long
arg3 long
arg4 long
arg5 long
Returns
int
Throws
ErrnoException

pread

Added in API level 21
int pread (FileDescriptor fd, 
                ByteBuffer buffer, 
                long offset)

See pread(2).

Parameters
fd FileDescriptor
buffer ByteBuffer
offset long
Returns
int
Throws
ErrnoException
InterruptedIOException

pread

Added in API level 21
int pread (FileDescriptor fd, 
                byte[] bytes, 
                int byteOffset, 
                int byteCount, 
                long offset)

See pread(2).

Parameters
fd FileDescriptor
bytes byte
byteOffset int
byteCount int
offset long
Returns
int
Throws
ErrnoException
InterruptedIOException

pwrite

Added in API level 21
int pwrite (FileDescriptor fd, 
                byte[] bytes, 
                int byteOffset, 
                int byteCount, 
                long offset)

See pwrite(2).

Parameters
fd FileDescriptor
bytes byte
byteOffset int
byteCount int
offset long
Returns
int
Throws
ErrnoException
InterruptedIOException

pwrite

Added in API level 21
int pwrite (FileDescriptor fd, 
                ByteBuffer buffer, 
                long offset)

See pwrite(2).

Parameters
fd FileDescriptor
buffer ByteBuffer
offset long
Returns
int
Throws
ErrnoException
InterruptedIOException

read

Added in API level 21
int read (FileDescriptor fd, 
                byte[] bytes, 
                int byteOffset, 
                int byteCount)

See read(2).

Parameters
fd FileDescriptor
bytes byte
byteOffset int
byteCount int
Returns
int
Throws
ErrnoException
InterruptedIOException

read

Added in API level 21
int read (FileDescriptor fd, 
                ByteBuffer buffer)

See read(2).

Parameters
fd FileDescriptor
buffer ByteBuffer
Returns
int
Throws
ErrnoException
InterruptedIOException

readlink

Added in API level 21
String readlink (String path)

See readlink(2).

Parameters
path String
Returns
String
Throws
ErrnoException

readv

Added in API level 21
int readv (FileDescriptor fd, 
                Object[] buffers, 
                int[] offsets, 
                int[] byteCounts)

See readv(2).

Parameters
fd FileDescriptor
buffers Object
offsets int
byteCounts int
Returns
int
Throws
ErrnoException
InterruptedIOException

recvfrom

Added in API level 21
int recvfrom (FileDescriptor fd, 
                byte[] bytes, 
                int byteOffset, 
                int byteCount, 
                int flags, 
                InetSocketAddress srcAddress)

See recvfrom(2).

Parameters
fd FileDescriptor
bytes byte
byteOffset int
byteCount int
flags int
srcAddress InetSocketAddress
Returns
int
Throws
ErrnoException
SocketException

recvfrom

Added in API level 21
int recvfrom (FileDescriptor fd, 
                ByteBuffer buffer, 
                int flags, 
                InetSocketAddress srcAddress)

See recvfrom(2).

Parameters
fd FileDescriptor
buffer ByteBuffer
flags int
srcAddress InetSocketAddress
Returns
int
Throws
ErrnoException
SocketException

remove

Added in API level 21
void remove (String path)

See remove(3).

Parameters
path String
Throws
ErrnoException

rename

Added in API level 21
void rename (String oldPath, 
                String newPath)

See rename(2).

Parameters
oldPath String
newPath String
Throws
ErrnoException

sendfile

Added in API level 21
long sendfile (FileDescriptor outFd, 
                FileDescriptor inFd, 
                MutableLong inOffset, 
                long byteCount)

See sendfile(2).

Parameters
outFd FileDescriptor
inFd FileDescriptor
inOffset MutableLong
byteCount long
Returns
long
Throws
ErrnoException

sendto

Added in API level 21
int sendto (FileDescriptor fd, 
                byte[] bytes, 
                int byteOffset, 
                int byteCount, 
                int flags, 
                InetAddress inetAddress, 
                int port)

See sendto(2).

Parameters
fd FileDescriptor
bytes byte
byteOffset int
byteCount int
flags int
inetAddress InetAddress
port int
Returns
int
Throws
ErrnoException
SocketException

sendto

Added in API level 21
int sendto (FileDescriptor fd, 
                ByteBuffer buffer, 
                int flags, 
                InetAddress inetAddress, 
                int port)

See sendto(2).

Parameters
fd FileDescriptor
buffer ByteBuffer
flags int
inetAddress InetAddress
port int
Returns
int
Throws
ErrnoException
SocketException

setegid

Added in API level 21
void setegid (int egid)

See setegid(2).

Parameters
egid int
Throws
ErrnoException

setenv

Added in API level 21
void setenv (String name, 
                String value, 
                boolean overwrite)

See setenv(3).

Parameters
name String
value String
overwrite boolean
Throws
ErrnoException

seteuid

Added in API level 21
void seteuid (int euid)

See seteuid(2).

Parameters
euid int
Throws
ErrnoException

setgid

Added in API level 21
void setgid (int gid)

See setgid(2).

Parameters
gid int
Throws
ErrnoException

setsid

Added in API level 21
int setsid ()

See setsid(2).

Returns
int
Throws
ErrnoException

setuid

Added in API level 21
void setuid (int uid)

See setuid(2).

Parameters
uid int
Throws
ErrnoException

shutdown

Added in API level 21
void shutdown (FileDescriptor fd, 
                int how)

See shutdown(2).

Parameters
fd FileDescriptor
how int
Throws
ErrnoException

socket

Added in API level 21
FileDescriptor socket (int domain, 
                int type, 
                int protocol)

See socket(2).

Parameters
domain int
type int
protocol int
Returns
FileDescriptor
Throws
ErrnoException

socketpair

Added in API level 21
void socketpair (int domain, 
                int type, 
                int protocol, 
                FileDescriptor fd1, 
                FileDescriptor fd2)

See socketpair(2).

Parameters
domain int
type int
protocol int
fd1 FileDescriptor
fd2 FileDescriptor
Throws
ErrnoException

stat

Added in API level 21
StructStat stat (String path)

See stat(2).

Parameters
path String
Returns
StructStat
Throws
ErrnoException

statvfs

Added in API level 21
StructStatVfs statvfs (String path)

See statvfs(2).

Parameters
path String
Returns
StructStatVfs
Throws
ErrnoException

strerror

Added in API level 21
String strerror (int errno)

See strerror(2).

Parameters
errno int
Returns
String

strsignal

Added in API level 21
String strsignal (int signal)

See strsignal(3).

Parameters
signal int
Returns
String

symlink

Added in API level 21
void symlink (String oldPath, 
                String newPath)

See symlink(2).

Parameters
oldPath String
newPath String
Throws
ErrnoException

sysconf

Added in API level 21
long sysconf (int name)

See sysconf(3).

Parameters
name int
Returns
long

tcdrain

Added in API level 21
void tcdrain (FileDescriptor fd)

See tcdrain(3).

Parameters
fd FileDescriptor
Throws
ErrnoException

tcsendbreak

Added in API level 21
void tcsendbreak (FileDescriptor fd, 
                int duration)

See tcsendbreak(3).

Parameters
fd FileDescriptor
duration int
Throws
ErrnoException

umask

Added in API level 21
int umask (int mask)

See umask(2).

Parameters
mask int
Returns
int

uname

Added in API level 21
StructUtsname uname ()

See uname(2).

Returns
StructUtsname

unsetenv

Added in API level 21
void unsetenv (String name)

See unsetenv(3).

Parameters
name String
Throws
ErrnoException

waitpid

Added in API level 21
int waitpid (int pid, 
                MutableInt status, 
                int options)

See waitpid(2).

Parameters
pid int
status MutableInt
options int
Returns
int
Throws
ErrnoException

write

Added in API level 21
int write (FileDescriptor fd, 
                ByteBuffer buffer)

See write(2).

Parameters
fd FileDescriptor
buffer ByteBuffer
Returns
int
Throws
ErrnoException
InterruptedIOException

write

Added in API level 21
int write (FileDescriptor fd, 
                byte[] bytes, 
                int byteOffset, 
                int byteCount)

See write(2).

Parameters
fd FileDescriptor
bytes byte
byteOffset int
byteCount int
Returns
int
Throws
ErrnoException
InterruptedIOException

writev

Added in API level 21
int writev (FileDescriptor fd, 
                Object[] buffers, 
                int[] offsets, 
                int[] byteCounts)

See writev(2).

Parameters
fd FileDescriptor
buffers Object
offsets int
byteCounts int
Returns
int
Throws
ErrnoException
InterruptedIOException

Hooray!