intro(2) 맨 페이지 - 윈디하나의 솔라나라
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개요
- 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
- MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
svcadm(1M)을 검색하려면 섹션
에서 1M 을 선택하고, 맨 페이지 이름
에 svcadm을 입력하고 검색을 누른다.
intro(2)
Intro(2) System Calls Intro(2)
NAME
Intro, intro - introduction to system calls and error numbers
SYNOPSIS
#include <errno.h>
DESCRIPTION
A system call is a C library function that requests a service from the
system, such as getting the time of day. This request is performed in
the kernel. The library interface executes a trap into the kernel,
which actually executes the system call code.
Most system calls return one or more error conditions. An error condi‐
tion is indicated by an otherwise impossible return value. This is
almost always −1 or the null pointer; the individual descriptions spec‐
ify the details. An error number is made available in the external
variable errno, which is not cleared on successful calls. So it is
tested only after an error has been indicated.
Every thread has a unique errno value specific to that thread. The
errno variable is implemented as a macro that references this per-
thread value. This errno macro can be used on either side of the
assignment as though it were a variable. Prior to the Oracle Solaris
11.4 release, it was necessary to specify the -mt option on the command
line at compilation time to enable the per-thread implementation of
errno. The -mt option is no longer required.
An error value listed as "will fail" describes a condition whose detec‐
tion and reporting is mandatory for an implementation that conforms to
the Single UNIX Specification (SUS). An application can rely on this
condition being detected and reported. An error value listed as "may
fail" describes a condition whose detection and reporting is optional
for an implementation that conforms to the SUS. An application should
not rely on this condition being detected and reported. An application
that relies on such behavior cannot be assured to be portable across
conforming implementations. If more than one error occurs in processing
a function call, any one of the possible errors may be returned, as the
order of detection is undefined. For more information regarding the
Single UNIX Specification, see the standards(7) man page.
Each system call description attempts to list all possible error num‐
bers. The following list gives the description of the error numbers and
their names as defined in <errno.h>.
1 EPERM Insufficient privileges
This error indicates an attempt to modify a file
in a way forbidden except to its owner or an
appropriately privileged process. It is also
returned when a process attempts to perform an
operation requiring a privilege not in its
effective set. See privileges(7).
The manual pages for individual functions docu‐
ment which privileges are needed to override the
restriction.
2 ENOENT No such file or directory
This error occurs when a file name is specified
but the file doesn't exist, or one of the direc‐
tories in the path name does not exist.
3 ESRCH No such process
This error occurs when no process can be found
in the system that corresponds to the specified
PID, LWPID_t, or thread_t.
4 EINTR Interrupted system call
This error occurs when an asynchronous signal
(such as interrupt or quit), which the user has
elected to catch, occurred during a system ser‐
vice function. If execution is resumed after
processing the signal, it will appear as if the
interrupted function call returned this error
condition.
In a multithreaded application, EINTR may be
returned whenever another thread or LWP calls
fork(2).
5 EIO I/O error
Some physical I/O error has occurred. In some
cases, this error may occur on a call following
the one to which it actually applies.
6 ENXIO No such device or address
This error occurs when I/O on a special file
refers to a subdevice which does not exist, or
exists beyond the limit of the device. It may
also occur when, for example, a tape drive is
not on-line or no disk pack is loaded on a
drive.
7 E2BIG Arg list too long
This error occurs when an argument list longer
than ARG_MAX bytes is presented to a member of
the exec family of functions (see exec(2)). The
argument list limit is the sum of the size of
the argument list plus the size of the environ‐
ment's exported shell variables.
8 ENOEXEC Exec format error
This error occurs when a request is made to exe‐
cute a file which, although it has the appropri‐
ate permissions, does not start with a valid
format (see a.out(5)).
9 EBADF Bad file number
This error occurs when either a file descriptor
refers to no open file, or a read(2) (respec‐
tively, write(2)) request is made to a file that
is open only for writing (respectively, read‐
ing).
10 ECHILD No child processes
This error occurs when a wait(3C) function call
is executed by a process that has no existing or
unwaited-for child processes.
11 EAGAIN Resource temporarily unavailable
This error occurs when no more of a given
resource, such as processes, LWPs, or memory, is
available, but may become available later when
other processes exit or otherwise reduce their
usage of the resource. For example, the fork(2)
function failed because the system's process ta‐
ble is full or the user is not allowed to create
any more processes, or a call failed because of
insufficient memory or swap space.
12 ENOMEM Cannot allocate memory
This error occurs during execution of brk() or
sbrk() (see brk(2)), or one of the exec family
of functions. A program asks for more space than
the system is able to supply. This is not a tem‐
porary condition; the maximum size is a system
parameter. On some architectures, the error may
also occur if the arrangement of text, data, and
stack segments requires too many segmentation
registers, or if there is not enough swap space
during the fork(2) function.
13 EACCES Permission denied
This error occurs when an attempt is made to
access a file in a way forbidden by the protec‐
tion system.
The manual pages for individual functions docu‐
ment the privileges that are needed to override
the protection system.
14 EFAULT Bad address
This error occurs when the system encounters a
hardware fault in attempting to use an argument
of a routine. For example, errno potentially may
be set to EFAULT any time a routine that takes a
pointer argument is passed an invalid address,
if the system can detect the condition. Since
systems differ in their ability to reliably
detect a bad address, on some implementations
passing a bad address to a routine will result
in undefined behavior. Examples of a bad address
include but are not limited to an address not
mapped into the user's address space or an
address with an incorrect ADI version. For more
information, see the adi(3C) man page.
15 ENOTBLK Block device required
This error occurs when a non-block device or
file is mentioned where a block device is
required (for example, in a call to the mount(2)
function).
16 EBUSY Device busy
This error occurs when an attempt is made to
mount a device that is already mounted or an
attempt is made to unmount a device on which
there is an active file (open file, current
directory, mounted-on file, active text seg‐
ment). It will also occur if an attempt is made
to enable accounting when it is already enabled.
The device or resource is currently unavailable.
EBUSY is also used by mutexes, semaphores, con‐
dition variables, and r/w locks, to indicate
that a lock is held, and by the processor con‐
trol function P_ONLINE.
17 EEXIST File exists
This error occurs when an existing file is men‐
tioned in an inappropriate context (for example,
call to the link(2) function).
18 EXDEV Cross-device link
This error occurs when a hard link to a file on
another device is attempted.
19 ENODEV No such device
This error occurs when an attempt is made to
apply an inappropriate operation to a device
(for example, read a write-only device).
20 ENOTDIR Not a directory
This error occurs when a non-directory is speci‐
fied where a directory is required (for example,
in a path prefix or as an argument to the
chdir(2) function).
21 EISDIR Is a directory
This error occurs when an attempt is made to
write on a directory.
22 EINVAL Invalid argument
This error occurs when an invalid argument is
specified (for example, unmounting a non-mounted
device), mentioning an undefined signal in a
call to the signal(3C) or kill(2) function, or
an unsupported operation related to extended
attributes is attempted.
23 ENFILE File table overflow
This error occurs when the system file table is
full (that is, SYS_OPEN files are open, and tem‐
porarily no more files can be opened).
24 EMFILE Too many open files
This error occurs when no process may have more
than OPEN_MAX file descriptors open at a time.
25 ENOTTY Inappropriate ioctl for device
This error occurs when a call was made to the
ioctl(2) function with a request that is not
valid for the given file descriptor, such as
specifying a file that is not a special charac‐
ter device, or specifying a request that is not
supported for the given device type.
26 ETXTBSY Text file busy (obsolete)
This error occurs when an attempt is made to
execute a pure-procedure program that is cur‐
rently open for writing. Also an attempt to open
for writing or to remove a pure-procedure pro‐
gram that is being executed. (This message is
obsolete.)
27 EFBIG File too large
This error occurs when the size of the file
exceeds the limit specified by resource
RLIMIT_FSIZEn; the file size exceeds the maximum
supported by the file system; or the file size
exceeds the offset maximum of the file descrip‐
tor. See the File Descriptor subsection of the
DEFINITIONS section below.
28 ENOSPC No space left on device
This error occurs while creating a directory
entry or writing an ordinary file, there is no
free space left on the device. In the fcntl(2)
function, the setting or removing of record
locks on a file cannot be accomplished because
there are no more record entries left on the
system.
29 ESPIPE Illegal seek
This error occurs when a call to the lseek(2)
function is issued to a pipe.
30 EROFS Read-only file system
This error occurs when an attempt to modify a
file or directory is made on a device mounted
read-only.
31 EMLINK Too many links
This error occurs an attempt to make more than
the maximum number of links, LINK_MAX, to a
file.
32 EPIPE Broken pipe
This error occurs when a write on a pipe for
which there is no process to read the data. This
condition normally generates a signal; the error
is returned if the signal is ignored.
33 EDOM Argument out of domain
This error occurs when the argument of a func‐
tion in the math package (3M) is out of the
domain of the function.
34 ERANGE Result too large
This error occurs when the value of a function
in the math package (3M) is not representable
within machine precision.
35 ENOMSG No message of desired type
This error occurs when an attempt is made to
receive a message of a type that does not exist
on the specified message queue (see msgrcv(2)).
36 EIDRM Identifier removed
This error is returned to processes that resume
execution due to the removal of an identifier
from the file system's name space (see
msgctl(2), semctl(2), and shmctl(2)).
37 ECHRNG Channel number out of range
38 EL2NSYNC Level 2 not synchronized
39 EL3HLT Level 3 halted
40 EL3RST Level 3 reset
41 ELNRNG Link number out of range
42 EUNATCH Protocol driver not attached
43 ENOCSI No CSI structure available
44 EL2HLT Level 2 halted
45 EDEADLK Deadlock situation detected/avoided
This error occurs when a deadlock situation is
detected and avoided. This error pertains to
file and record locking, and also applies to
mutexes, semaphores, condition variables, and
r/w locks.
46 ENOLCK No record locks available
This error occurs when there are no more locks
available. The system lock table is full (see
fcntl(2)).
47 ECANCELED Operation canceled
This error occurs when the associated asynchro‐
nous operation is canceled before completion.
48 ENOTSUP Operation not supported
This error occurs when this version of the sys‐
tem does not support the feature. Future ver‐
sions of the system may provide support.
49 EDQUOT Disc quota exceeded
A write(2) to an ordinary file, the creation of
a directory or symbolic link, or the creation of
a directory entry failed because the user's
quota of disk blocks was exhausted, or the allo‐
cation of an inode for a newly created file
failed because the user's quota of inodes was
exhausted.
50 ECKSUM Checksum failure
51 EFRAGS Too fragmented
52 EXFULL Message tables full
53 ENOKEY Cryptographic key not available
58 EOWNERDEAD Owner of the lock died
An attempt to acquire a robust mutex succeeded,
but the state protected by the mutex may be
inconsistent as the prior owner terminated with‐
out unlocking it. See mutex_init(3C) for further
information.
59 ENOTRECOVERABLE Lock is not recoverable
An attempt to acquire a robust mutex failed as a
previous owner terminated without unlocking it,
and the prior owner was unable to make the state
it protects be consistent again. See
mutex_init(3C) for further information.
60 ENOSTR Not a stream device
A putmsg(2) or getmsg(2) call was attempted on a
file descriptor that is not a STREAMS device.
61 ENODATA No data available
62 ETIME Timer expired
This error occurs when the timer set for a
STREAMS ioctl(2) call has expired. The cause of
this error is device-specific and could indicate
either a hardware or software failure, or per‐
haps a timeout value that is too short for the
specific operation. The status of the ioctl()
operation is indeterminate. This is also
returned in the case of _lwp_cond_timedwait(2)
or cond_timedwait(3C).
63 ENOSR Out of stream resources
During a STREAMS open(2) call, either no
STREAMS queues or no STREAMS head data struc‐
tures were available. This is a temporary condi‐
tion; one may recover from it if other processes
release resources.
64 ENONET Machine is not on the network
65 ENOPKG Package not installed
This error occurs when users attempt to use a
call from a package which has not been
installed.
66 EREMOTE Object is remote
This error occurs when users try to share a
resource that is not on the local machine, or
try to mount(2) or umount(2) a device or path
name that is on a remote machine.
67 ENOLINK Link has been severed
An operation on a file failed because the file
is on a remote machine and the link to that
machine is no longer active.
68 EADV Advertise error (obsolete)
This error is RFS (Remote File System) specific.
It occurs when users try to advertise a resource
already advertised, try to stop RFS while there
are resources still advertised, or try to force‐
ably unmount a resource that is still adver‐
tised.
69 ESRMNT Srmount error (obsolete)
This error is RFS (Remote File System) specific.
It occurs when an attempt is made to stop RFS
while resources are still mounted by remote
machines, or when a resource is readvertised
with a client list that does not include a
remote machine with the resource currently
mounted.
70 ECOMM Communication error on send
An operation on a file failed because the file
is on a remote machine and the link to that
machine is no longer active.
71 EPROTO Protocol error
This error occurs when some protocol error
occurs. This error is device-specific, but is
generally not related to a hardware failure.
72 ELOCKUNMAPPED Locked lock was unmapped (obsolete)
An obsolete error message, since replaced by
EOWNERDEAD. See mutex_init(3C) for further
information.
73 ENOTACTIVE Facility is not active
A system call failed because it required a
facillity, such as Extended Accounting, that was
not active.
74 EMULTIHOP Multihop attempted
A call failed because components of a file path
require hopping to multiple remote machines and
the file system does not allow it.
75 EADI Application Data Integrity mismatch detected
This error occurs when an ADI version mismatch
is detected when the system attempts to read or
write data to an ADI-enabled location that is
part of a buffer used for I/O. See adi(7).
77 EBADMSG Not a data message
During a read(2), getmsg(2), or ioctl(2)
I_RECVFD call to a STREAMS device, something has
come to the head of the queue that cannot be
processed. That something depends on the call:
read(): control information or passed file
descriptor.
getmsg(): passed file descriptor.
ioctl(): control or data information.
78 ENAMETOOLONG File name too long
This error occurs when the length of the path
argument exceeds PATH_MAX, or the length of a
path component exceeds NAME_MAX while
_POSIX_NO_TRUNC is in effect; see lim‐
its.h(3HEAD).
79 EOVERFLOW Value too large for defined data type
This error occurs when a value is outside of the
range defined for the data type it is to be
stored in.
80 ENOTUNIQ Name not unique on network
This error occurs when a given log name is not
unique.
81 EBADFD File descriptor in bad state
This error occurs when either a file descriptor
refers to no open file or a read request is made
to a file that is open only for writing.
82 EREMCHG Remote address changed
83 ELIBACC Cannot access a needed shared library (obsolete)
Trying to exec an a.out that requires a static
shared library and the static shared library
does not exist or the user does not have permis‐
sion to use it.
84 ELIBBAD Accessing a corrupted shared library (obsolete)
Trying to exec an a.out that requires a static
shared library (to be linked in) and exec could
not load the static shared library. The static
shared library is probably corrupted.
85 ELIBSCN .lib section in a.out corrupted (obsolete)
Trying to exec an a.out that requires a static
shared library (to be linked in) and there was
erroneous data in the .lib section of the a.out.
The .lib section tells exec what static shared
libraries are needed. The a.out is probably cor‐
rupted.
86 ELIBMAX Attempting to link in more shared libraries than
system limit (obsolete)
Trying to exec an a.out that requires more
static shared libraries than is allowed on the
current configuration of the system.
87 ELIBEXEC Cannot exec a shared library directly (obsolete)
This error occurs while attempting to exec a
shared library directly.
88 EILSEQ Illegal byte sequence
This error occurs if there is a byte sequence
that is not valid for the expected character
encoding.
89 ENOSYS Operation not applicable
90 ELOOP Number of symbolic links encountered during path
name traversal exceeds MAXSYMLINKS
91 ERESTART Restartable system call
This error occurs when an interrupted system
call should be restarted (not externally visi‐
ble).
92 ESTRPIPE If pipe/FIFO, don't sleep in stream head
Streams pipe error (not externally visible).
93 ENOTEMPTY Directory not empty
94 EUSERS Too many users
95 ENOTSOCK Socket operation on non-socket
96 EDESTADDRREQ Destination address required
This error occurs when a required address is
omitted from an operation on a transport end‐
point. Destination address is required.
97 EMSGSIZE Message too long
This error occurs when a message sent on a
transport provider is larger than the internal
message buffer or some other network limit.
98 EPROTOTYPE Protocol wrong type for socket
This error occurs when a protocol specified does
not support the semantics of the socket type
requested.
99 ENOPROTOOPT Option not supported by protocol
This error occurs when a bad option or level is
specified when getting or setting options for a
protocol.
120 EPROTONOSUPPORT Protocol not supported
The protocol has not been configured into the
system or no implementation for it exists.
121 ESOCKTNOSUPPORT Socket type not supported
The support for the socket type has not been
configured into the system or no implementation
for it exists.
122 EOPNOTSUPP Operation not supported on transport endpoint
For example, trying to accept a connection on a
datagram transport endpoint.
123 EPFNOSUPPORT Protocol family not supported
The protocol family has not been configured into
the system or no implementation for it exists.
Used for the Internet protocols.
124 EAFNOSUPPORT Address family not supported by protocol family
This error occurs when an address incompatible
with the requested protocol is used.
125 EADDRINUSE Address already in use
This error occurs when a user attempts to use an
address already in use, and the protocol does
not allow this.
126 EADDRNOTAVAIL Cannot assign requested address
Results from an attempt to create a transport
endpoint with an address not on the current
machine.
127 ENETDOWN Network is down
Operation encountered a dead network.
128 ENETUNREACH Network is unreachable
Operation was attempted to an unreachable net‐
work.
129 ENETRESET Network dropped connection because of reset
This error occurs when the host you are con‐
nected to crashes and reboots.
130 ECONNABORTED Software caused connection abort
A connection abort was caused internal to your
host machine.
131 ECONNRESET Connection reset by peer
A connection was forcibly closed by a peer. This
normally results from a loss of the connection
on the remote host due to a timeout or a reboot.
132 ENOBUFS No buffer space available
This error occurs when an operation on a trans‐
port endpoint or pipe is not performed because
the system lacked sufficient buffer space or
because a queue is full.
133 EISCONN Transport endpoint is already connected
This error occurs when a connect request is made
on an already connected transport endpoint; or,
a sendto() or sendmsg() request on a connected
transport endpoint specified a destination when
already connected.
134 ENOTCONN Transport endpoint is not connected
This error occurs when a request to send or
receive data is disallowed because the transport
endpoint is not connected and (when sending a
datagram) no address was supplied.
143 ESHUTDOWN Cannot send after socket shutdown
This error occurs when a request to send data is
disallowed because the transport endpoint has
already been shut down.
144 ETOOMANYREFS Too many references: cannot splice
145 ETIMEDOUT Connection timed out
This error occurs when a connect or send request
fails because the connected party does not prop‐
erly responds after a period of time; or a write
or fsync request fails because a file is on an
NFS file system mounted with the soft option.
146 ECONNREFUSED Connection refused
This error occurs when no connection could be
made because the target machine actively refused
it. This usually results from trying to connect
to a service that is inactive on the remote
host.
147 EHOSTDOWN Host is down
This error occurs when a transport provider
operation fails because the destination host is
down.
148 EHOSTUNREACH No route to host
This error occurs when a transport provider
operation is attempted to an unreachable host.
149 EALREADY Operation already in progress
This error occurs when an operation is attempted
on a non-blocking object that already has an
operation in progress.
150 EINPROGRESS Operation now in progress
This error occurs when an operation that takes a
long time to complete (such as a connect()) is
attempted on a non-blocking object.
151 ESTALE Stale NFS file handle
A file or directory that was opened by an NFS
client was either removed or replaced on the
server.
DEFINITIONS
Background Process Group
Any process group that is not the foreground process group of a session
that has established a connection with a controlling terminal.
Controlling Process
A session leader that established a connection to a controlling termi‐
nal.
Controlling Terminal
A terminal that is associated with a session. Each session may have, at
most, one controlling terminal associated with it and a controlling
terminal may be associated with only one session. Certain input
sequences from the controlling terminal cause signals to be sent to
process groups in the session associated with the controlling terminal.
For more information, see the termio(4I) man page.
Directory
Directories organize files into a hierarchical system where directories
are the nodes in the hierarchy. A directory is a file that catalogs the
list of files, including directories (sub-directories), that are
directly beneath it in the hierarchy. Entries in a directory file are
called links. A link associates a file identifier with a filename. By
convention, a directory contains at least two links, . (dot) and ..
(dot-dot). The link called dot refers to the directory itself while
dot-dot refers to its parent directory. The root directory, which is
the top-most node of the hierarchy, has itself as its parent directory.
The pathname of the root directory is / and the parent directory of the
root directory is /.
Downstream
The direction from the stream head to the driver in a stream.
Driver
In a stream, the driver provides the interface between peripheral hard‐
ware and the stream. A driver can also be a pseudo-driver, such as a
multiplexor or log driver (see log(4D)), which is not associated with a
hardware device.
Effective User ID and Effective Group ID
An active process has an effective user ID and an effective group ID
that are used to determine file access permissions (see below). The
effective user ID and effective group ID are equal to the process's
real user ID and real group ID, respectively, unless the process or one
of its ancestors evolved from a file that had the set-user-ID bit or
set-group-ID bit set (see exec(2)).
File Access Permissions
Read, write, and execute/search permissions for a file are granted to a
process if one or more of the following conditions are true:
o The effective user ID of the process matches the user ID of
the owner of the file and the appropriate access bit of the
"owner" portion (0700) of the file mode is set.
o The effective user ID of the process does not match the user
ID of the owner of the file, but either the effective group
ID or one of the supplementary group IDs of the process
match the group ID of the file and the appropriate access
bit of the "group" portion (0070) of the file mode is set.
o The effective user ID of the process does not match the user
ID of the owner of the file, and neither the effective group
ID nor any of the supplementary group IDs of the process
match the group ID of the file, but the appropriate access
bit of the "other" portion (0007) of the file mode is set.
o The read, write, or execute mode bit is not set but the
process has the discretionary file access override privilege
for the corresponding mode bit: {PRIV_FILE_DAC_READ} for the
read bit, {PRIV_FILE_DAC_WRITE} for the write bit,
{PRIV_FILE_DAC_SEARCH} for the execute bit on directories,
and {PRIV_FILE_DAC_EXECUTE} for the executable bit on plain
files.
o The file has an Access Control List (ACL) with an entry
granting permission to the user or group of the process. See
acl(7) for details.
Otherwise, the corresponding permissions are denied.
File Descriptor
A file descriptor is a small integer used to perform I/O operations on
a file. The value of a file descriptor is from 0 to (NOFILES−1). A
process may have no more than NOFILES file descriptors open simultane‐
ously. A file descriptor is returned by calls such as open(2) or
pipe(2). The file descriptor is used as an argument by calls such as
read(2), write(2), ioctl(2), and close(2).
Each file descriptor has a corresponding offset maximum. For regular
files that are opened without setting the O_LARGEFILE flag, the offset
maximum is 2 Gbyte − 1 byte (2^31 −1 bytes). For regular files that are
opened with the O_LARGEFILE flag set, the offset maximum is 2^63 −1
bytes.
File Name
Names consisting of 1 to NAME_MAX characters are used to name an ordi‐
nary file, special file or directory.
These characters are selected from the set of all character values
excluding \0 (null) and the ASCII code for / (slash).
Note that it is generally unwise to use *, ?, [, or ] as part of file
names because of the special meaning attached to these characters by
the shell (see sh(1), csh(1), and ksh(1)). Although permitted, the use
of unprintable characters in file names should be avoided.
A file name is sometimes referred to as a pathname component. The
interpretation of a pathname component is dependent on the values of
NAME_MAX and _POSIX_NO_TRUNC associated with the path prefix of that
component. If any pathname component longer than NAME_MAX and
_POSIX_NO_TRUNC is in effect for the path prefix of that component (see
fpathconf(2) and limits.h(3HEAD)), it shall be considered an error con‐
dition in that implementation. Otherwise, the implementation shall use
the first NAME_MAX bytes of the pathname component.
Foreground Process Group
Each session that has established a connection with a controlling ter‐
minal will distinguish one process group of the session as the fore‐
ground process group of the controlling terminal. This group has cer‐
tain privileges when accessing its controlling terminal that are denied
to background process groups.
{IOV_MAX}
Maximum number of entries in a struct iovec array.
{LIMIT}
The braces notation, {LIMIT}, is used to denote a magnitude limitation
imposed by the implementation. This indicates a value which may be
defined by a header file (without the braces), or the actual value may
be obtained at runtime by a call to the configuration inquiry path‐
conf(2) with the name argument _PC_LIMIT.
Masks
The file mode creation mask of the process used during any create func‐
tion calls to turn off permission bits in the mode argument supplied.
Bit positions that are set in umask(cmask) are cleared in the mode of
the created file.
Message
In a stream, one or more blocks of data or information, with associated
STREAMS control structures. Messages can be of several defined types,
which identify the message contents. Messages are the only means of
transferring data and communicating within a stream.
Message Queue
In a stream, a linked list of messages awaiting processing by a module
or driver.
Message Queue Identifier
A message queue identifier (msqid) is a unique positive integer created
by a msgget(2) call. Each msqid has a message queue and a data struc‐
ture associated with it. The data structure is referred to as msqid_ds
and contains the following members:
struct ipc_perm msg_perm;
struct msg *msg_first;
struct msg *msg_last;
ulong_t msg_cbytes;
ulong_t msg_qnum;
ulong_t msg_qbytes;
pid_t msg_lspid;
pid_t msg_lrpid;
time_t msg_stime;
time_t msg_rtime;
time_t msg_ctime;
The following information describes the msqid_ds structure members:
The msg_perm member is an ipc_perm structure that specifies the message
operation permission (see below). This structure includes the following
members:
uid_t cuid; /* creator user id */
gid_t cgid; /* creator group id */
uid_t uid; /* user id */
gid_t gid; /* group id */
mode_t mode; /* r/w permission */
ulong_t seq; /* slot usage sequence # */
key_t key; /* key */
The *msg_first member is a pointer to the first message on the queue.
The *msg_last member is a pointer to the last message on the queue.
The msg_cbytes member is the current number of bytes on the queue.
The msg_qnum member is the number of messages currently on the queue.
The msg_qbytes member is the maximum number of bytes allowed on the
queue.
The msg_lspid member is the process ID of the last process that per‐
formed a msgsnd() operation.
The msg_lrpid member is the process id of the last process that per‐
formed a msgrcv() operation.
The msg_stime member is the time of the last msgsnd() operation.
The msg_rtime member is the time of the last msgrcv() operation.
The msg_ctime member is the time of the last msgctl() operation that
changed a member of the above structure.
Message Operation Permissions
In the msgctl(2), msgget(2), msgrcv(2), and msgsnd(2) function descrip‐
tions, the permission required for an operation is given as {token},
where token is the type of permission needed, interpreted as follows:
00400 READ by user
00200 WRITE by user
00040 READ by group
00020 WRITE by group
00004 READ by others
00002 WRITE by others
Read and write permissions for a msqid are granted to a process if one
or more of the following conditions are true:
o The {PRIV_IPC_DAC_READ} or {PRIV_IPC_DAC_WRITE} privilege is
present in the effective set.
o The effective user ID of the process matches msg_perm.cuid
or msg_perm.uid in the data structure associated with msqid
and the appropriate bit of the "user" portion (0600) of
msg_perm.mode is set.
o Any group ID in the process credentials from the set matches
msg_perm.cgid or msg_perm.gid and the appropriate bit of the
"group" portion (060) of msg_perm.mode is set.
o The appropriate bit of the "other" portion (006) of
msg_perm.mode is set."
Otherwise, the corresponding permissions are denied.
Module
A module is an entity containing processing routines for input and out‐
put data. It always exists in the middle of a stream, between the
stream's head and a driver. A module is the STREAMS counterpart to the
commands in a shell pipeline except that a module contains a pair of
functions which allow independent bidirectional (downstream and
upstream) data flow and processing.
Multiplexor
A multiplexor is a driver that allows streams associated with several
user processes to be connected to a single driver, or several drivers
to be connected to a single user process. STREAMS does not provide a
general multiplexing driver, but does provide the facilities for con‐
structing them and for connecting multiplexed configurations of
streams.
Offset Maximum
An offset maximum is an attribute of an open file description repre‐
senting the largest value that can be used as a file offset.
Orphaned Process Group
A process group in which the parent of every member in the group is
either itself a member of the group, or is not a member of the process
group's session.
Parent Process ID
A new process is created by a currently active process (see fork(2)).
The parent process ID of a process is the process ID of its creator.
Path Name
A path name is a null-terminated character string starting with an
optional slash (/), followed by zero or more directory names separated
by slashes, optionally followed by a file name.
If a path name begins with a slash, the path search begins at the root
directory. Otherwise, the search begins from the current working direc‐
tory.
A slash by itself names the root directory.
Unless specifically stated otherwise, the null path name is treated as
if it named a non-existent file.
Privilege
Having appropriate privileges means having the capability to override
system restrictions. On Solaris, these are represented as sets of priv‐
ileges that provide fine-grained control over the actions a process can
take. Specific privileges are denoted in man pages as {PRIV_NAME}, and
are listed and defined in the privileges(7) man page. When referenced
in source code, the braces are not included.
Privileged User
Solaris software implements a set of privileges that provide fine-
grained control over the actions of processes. The possession of a cer‐
tain privilege allows a process to perform a specific set of restricted
operations. Prior to the Oracle Solaris 10 release, a process running
with uid 0 was granted all privileges. See privileges(7) for the seman‐
tics and the degree of backward compatibility awarded to processes with
an effective uid of 0.
Process Group
Each process in the system is a member of a process group that is iden‐
tified by a process group ID. Any process that is not a process group
leader may create a new process group and become its leader. Any
process that is not a process group leader may join an existing process
group that shares the same session as the process. A newly created
process joins the process group of its parent.
Process Group Leader
A process group leader is a process whose process ID is the same as its
process group ID.
Process Group ID
Each active process is a member of a process group and is identified by
a positive integer called the process group ID. This ID is the process
ID of the group leader. This grouping permits the signaling of related
processes (for more information, see kill(2) man page).
Process ID
Each process in the system is uniquely identified during its lifetime
by a positive integer called a process ID. A process ID cannot be
reused by the system until the process lifetime, process group life‐
time, and session lifetime ends for any process ID, process group ID,
and session ID equal to that process ID. There are threads within a
process with thread IDs thread_t and LWPID_t. These threads are not
visible to the outside process.
Process Lifetime
A process lifetime begins when the process is forked and ends after it
exits, when its termination has been acknowledged by its parent
process. For more information, see wait(3C) man page.
Process Group Lifetime
A process group lifetime begins when the process group is created by
its process group leader, and ends when the lifetime of the last
process in the group ends or when the last process in the group leaves
the group.
Processor Set ID
The processors in a system may be divided into subsets, known as pro‐
cessor sets. A process bound to one of these sets will run only on pro‐
cessors in that set, and the processors in the set will normally run
only processes that have been bound to the set. Each active processor
set is identified by a positive integer. For more information, see
pset_create(2) man page.
Read Queue
In a stream, the message queue in a module or driver containing mes‐
sages moving upstream.
Real User ID and Real Group ID
Each user allowed on the system is identified by a positive integer (0
to MAXUID) called a real user ID.
Each user is also a member of a group. The group is identified by a
positive integer called the real group ID.
An active process has a real user ID and real group ID that are set to
the real user ID and real group ID, respectively, of the user responsi‐
ble for the creation of the process.
Root Directory and Current Working Directory
Each process has associated with it a concept of a root directory and a
current working directory for the purpose of resolving path name
searches. The root directory of a process need not be the root direc‐
tory of the root file system.
Saved Resource Limits
Saved resource limits is an attribute of a process that provides some
flexibility in the handling of unrepresentable resource limits, as
described in the exec family of functions and setrlimit(2).
Saved User ID and Saved Group ID
The saved user ID and saved group ID are the values of the effective
user ID and effective group ID just after an exec of a file whose set
user or set group file mode bit has been set (see exec(2)).
Semaphore Identifier
A semaphore identifier (semid) is a unique positive integer created by
a semget(2) call. Each semid has a set of semaphores and a data struc‐
ture associated with it. The data structure is referred to as semid_ds
and contains the following members:
struct ipc_perm sem_perm; /* operation permission struct */
struct sem *sem_base; /* ptr to first semaphore in set */
ushort_t sem_nsems; /* number of sems in set */
time_t sem_otime; /* last operation time */
time_t sem_ctime; /* last change time */
/* Times measured in secs since */
/* 00:00:00 GMT, Jan. 1, 1970 */
The following are descriptions of the semid_ds structure members:
The sem_perm member is an ipc_perm structure that specifies the sema‐
phore operation permission (see below). This structure includes the
following members:
uid_t uid; /* user id */
gid_t gid; /* group id */
uid_t cuid; /* creator user id */
gid_t cgid; /* creator group id */
mode_t mode; /* r/a permission */
ulong_t seq; /* slot usage sequence number */
key_t key; /* key */
The sem_nsems member is equal to the number of semaphores in the set.
Each semaphore in the set is referenced by a nonnegative integer
referred to as a sem_num. sem_num values run sequentially from 0 to the
value of sem_nsems minus 1.
The sem_otime member is the time of the last semop(2) operation.
The sem_ctime member is the time of the last semctl(2) operation that
changed a member of the above structure.
A semaphore is a data structure called sem that contains the following
members:
ushort_t semval; /* semaphore value */
pid_t sempid; /* pid of last operation */
ushort_t semncnt; /* # awaiting semval > cval */
ushort_t semzcnt; /* # awaiting semval = 0 */
The following information describes the sem structure members:
The semval member is a non-negative integer that is the actual value of
the semaphore.
The sempid member is equal to the process ID of the last process that
performed a semaphore operation on this semaphore.
The semncnt member is a count of the number of processes that are cur‐
rently suspended awaiting this semaphore's semval to become greater
than its current value.
The semzcnt member is a count of the number of processes that are cur‐
rently suspended awaiting this semaphore's semval to become 0.
Semaphore Operation Permissions
In the semop(2) and semctl(2) function descriptions, the permission
required for an operation is given as {token}, where token is the type
of permission needed interpreted as follows:
00400 READ by user
00200 ALTER by user
00040 READ by group
00020 ALTER by group
00004 READ by others
00002 ALTER by others
Read and alter permissions for a semid are granted to a process if one
or more of the following conditions are true:
o The {PRIV_IPC_DAC_READ} or {PRIV_IPC_DAC_WRITE} privilege is
present in the effective set.
o The effective user ID of the process matches sem_perm.cuid
or sem_perm.uid in the data structure associated with semid
and the appropriate bit of the "user" portion (0600) of
sem_perm.mode is set.
o The effective group ID of the process matches sem_perm.cgid
or sem_perm.gid and the appropriate bit of the "group" por‐
tion (060) of sem_perm.mode is set.
o The appropriate bit of the "other" portion (06) of
sem_perm.mode is set.
Otherwise, the corresponding permissions are denied.
Session
A session is a group of processes identified by a common ID called a
session ID, capable of establishing a connection with a controlling
terminal. Any process that is not a process group leader may create a
new session and process group, becoming the session leader of the ses‐
sion and process group leader of the process group. A newly created
process joins the session of its creator.
Session ID
Each session in the system is uniquely identified during its lifetime
by a positive integer called a session ID, the process ID of its ses‐
sion leader.
Session Leader
A session leader is a process whose session ID is the same as its
process and process group ID.
Session Lifetime
A session lifetime begins when the session is created by its session
leader, and ends when the lifetime of the last process that is a member
of the session ends, or when the last process that is a member in the
session leaves the session.
Shared Memory Identifier
A shared memory identifier (shmid) is a unique positive integer created
by a shmget(2) or shmget_osm(2) call. Each shmid has a segment of mem‐
ory (referred to as a shared memory segment) and a data structure asso‐
ciated with it. (Note that these shared memory segments must be explic‐
itly removed by the user after the last reference to them is removed.)
The data structure is referred to as shmid_ds and contains the follow‐
ing members:
struct ipc_perm shm_perm; /* operation permission struct */
size_t shm_segsz; /* size of segment */
struct anon_map *shm_amp; /* ptr to region structure */
char pad[4]; /* for swap compatibility */
pid_t shm_lpid; /* pid of last operation */
pid_t shm_cpid; /* creator pid */
uintptr_t shm_flags; /* see below */
uint64_t shm_gransize; /* shared memory granule size */
uint64_t shm_allocated;/* shared memory amount allocated */
shmatt_t shm_nattch; /* number of current attaches */
ulong_t shm_cnattch; /* used only for shminfo */
time_t shm_atime; /* last attach time */
time_t shm_dtime; /* last detach time */
time_t shm_ctime; /* last change time */
/* Times measured in secs since */
/* 00:00:00 GMT, Jan. 1, 1970 */
The following information describes the shmid_ds structure members:
The shm_perm member is an ipc_perm structure that specifies the shared
memory operation permission (see below). This structure includes the
following members:
uid_t cuid; /* creator user id */
gid_t cgid; /* creator group id */
uid_t uid; /* user id */
gid_t gid; /* group id */
mode_t mode; /* r/w permission */
ulong_t seq; /* slot usage sequence # */
key_t key; /* key */
The shm_segsz member specifies the size of the shared memory segment in
bytes.
The shm_cpid member is the process ID of the process that creates the
shared memory identifier.
The shm_lpid member is the process ID of the last process that per‐
formed a shmat() or shmdt() operation (see shmop(2)).
If shm_flags has the SHMDS_GRANULE bit set, then the shared memory seg‐
ment was created using shmget_osm(2), and the shm_gransize and
shm_allocated members are valid. The shm_gransize member contains the
allocation granule for the segment, and the shm_allocated member con‐
tains the amount of memory allocated inside the segment. If shm_flags
does not have the SHMDS_GRANULE bit set, then the shm_gransize and
shm_allocated members have undefined contents.
The shm_nattch member is the number of processes that currently have
this segment attached.
The shm_atime member is the time of the last shmat() operation (for
more information, see shmop(2) man page).
The shm_dtime member is the time of the last shmdt() operation (for
more information, see shmop(2) man page).
The shm_ctime member is the time of the last shmctl(2) operation that
changed one of the members of the above structure.
Shared Memory Operation Permissions
In the shmctl(2), shmat(), and shmdt() (see shmop(2)) function descrip‐
tions, the permission required for an operation is given as {token},
where token is the type of permission needed and it is interpreted as
follows:
00400 READ by user
00200 WRITE by user
00040 READ by group
00020 WRITE by group
00004 READ by others
00002 WRITE by others
Read and write permissions for a shmid are granted to a process if one
or more of the following conditions are true:
o The {PRIV_IPC_DAC_READ} or {PRIV_IPC_DAC_WRITE} privilege is
present in the effective set.
o The effective user ID of the process matches shm_perm.cuid
or shm_perm.uid in the data structure associated with shmid
and the appropriate bit of the "user" portion (0600) of
shm_perm.mode is set.
o The effective group ID of the process matches shm_perm.cgid
or shm_perm.gid and the appropriate bit of the "group" por‐
tion (060) of shm_perm.mode is set.
o The appropriate bit of the "other" portion (06) of
shm_perm.mode is set.
Otherwise, the corresponding permissions are denied.
Special Processes
The process with ID 0 and the process with ID 1 are special processes
referred to as proc0 and proc1; see kill(2). proc0 is the process
scheduler. proc1 is the initialization process (init); proc1 is the
ancestor of every other process in the system and is used to control
the process structure.
STREAMS
A set of kernel mechanisms that support the development of network ser‐
vices and data communication drivers. It defines interface standards
for character I/O within the kernel and between the kernel and user
level processes. The STREAMS mechanism is composed of utility routines,
kernel facilities, and a set of data structures.
Stream
A stream is a full-duplex data path within the kernel between a user
process and driver routines. The primary components of a stream are a
stream head, a driver, and zero or more modules between the stream head
and driver. A stream is analogous to a shell pipeline, except that data
flow and processing are bidirectional.
Stream Head
In a stream, the stream head is the end of the stream that provides the
interface between the stream and a user process. The principal func‐
tions of the stream head are processing STREAMS-related system calls
and passing data and information between a user process and the stream.
Upstream
The direction from driver to stream head in a stream.
Write Queue
In a stream, the message queue in a module or driver containing mes‐
sages moving downstream.
ACKNOWLEDGMENTS
Oracle gratefully acknowledges The Open Group for permission to repro‐
duce portions of its copyrighted documentation. Original documentation
from The Open Group can be obtained online at https://publica‐
tions.opengroup.org/.
The Institute of Electrical and Electronics Engineers and The Open
Group, have given us permission to reprint portions of their documenta‐
tion.
In the following statement, the phrase "this text" refers to portions
of the system documentation.
Portions of this text are reprinted and reproduced in electronic form
in the Oracle Solaris Reference Manual, from IEEE Std 1003.1, 2004 Edi‐
tion, Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6, Copy‐
right © 2001-2004 by the Institute of Electrical and Electronics Engi‐
neers, Inc and The Open Group. In the event of any discrepancy between
these versions and the original IEEE and The Open Group Standard, the
original IEEE and The Open Group Standard is the referee document. The
original Standard can be obtained online at https://www.open‐
group.org/unix.
This notice shall appear on any product containing this material.
SEE ALSO
acl(7), privileges(7), resource-controls(7), standards(7), threads(7)
Oracle Solaris 11.4 3 Nov 2021 Intro(2)
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