path: root/usr/src/man/man2/Intro.2

'\" te
.\" Copyright 1989 AT&T.
.\" Copyright (c) 2008, Sun Microsystems, Inc.  All Rights Reserved.
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
.\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
.TH INTRO 2 "Nov 17, 2008"
.SH NAME
Intro, intro \- introduction to system calls and error numbers
.SH SYNOPSIS
.LP
.nf
\fB#include <errno.h>\fR
.fi

.SH DESCRIPTION
.sp
.LP
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.
.sp
.LP
Most system calls return one or more error conditions. An error condition is
indicated by an otherwise impossible return value. This is almost always
\fB\(mi1\fR or the null pointer; the individual descriptions specify the
details. An error number is also made available in the external variable
\fBerrno\fR, which is not cleared on successful calls, so it should be tested
only after an error has been indicated.
.sp
.LP
In the case of multithreaded applications, the \fB-mt\fR option must be
specified on the command line at compilation time (see \fBthreads\fR(7)). When
the \fB-mt\fR option is specified, \fBerrno\fR becomes a macro that enables
each thread to have its own \fBerrno\fR. This \fBerrno\fR macro can be used on
either side of the assignment as though it were a variable.
.sp
.LP
An error value listed as "will fail" describes a condition whose detection 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 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 might may be returned, as the
order of detection is undefined. See \fBstandards\fR(7) for additional
information regarding the Single UNIX Specification.
.sp
.LP
Each system call description attempts to list all possible error numbers. The
following is a complete list of the error numbers and their names as defined in
<\fBerrno.h\fR>.
.sp
.ne 2
.na
\fB1 EPERM\fR
.ad
.RS 23n
Lacking appropriate privileges
.sp
Typically this error indicates an attempt to modify a file in some way
forbidden except to its owner or an appropriately privileged process.  It is
also returned for attempts by ordinary users to perform operations allowed only
to processes with certain privileges.
.sp
The manual pages for individual functions document which privileges are needed
to override the restriction.
.RE

.sp
.ne 2
.na
\fB2 ENOENT\fR
.ad
.RS 23n
No such file or directory
.sp
A file name is specified and the file should exist but doesn't, or one of the
directories in a path name does not exist.
.RE

.sp
.ne 2
.na
\fB3 ESRCH\fR
.ad
.RS 23n
No such process, LWP, or thread
.sp
No process can be found in the system that corresponds to the specified
\fBPID,\fR \fBLWPID_t\fR, or \fBthread_t\fR.
.RE

.sp
.ne 2
.na
\fB4 EINTR\fR
.ad
.RS 23n
Interrupted system call
.sp
An asynchronous signal (such as interrupt or quit), which the user has elected
to catch, occurred during a system service function. If execution is resumed
after processing the signal, it will appear as if the interrupted function call
returned this error condition.
.sp
In a multithreaded application, \fBEINTR\fR may be returned whenever another
thread or \fBLWP\fR calls \fBfork\fR(2).
.RE

.sp
.ne 2
.na
\fB5 EIO\fR
.ad
.RS 23n
I/O error
.sp
Some physical I/O error has occurred. This error may in some cases occur on a
call following the one to which it actually applies.
.RE

.sp
.ne 2
.na
\fB6 ENXIO\fR
.ad
.RS 23n
No such device or address
.sp
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.
.RE

.sp
.ne 2
.na
\fB7 E2BIG\fR
.ad
.RS 23n
Arg list too long
.sp
An argument list longer than  \fBARG_MAX\fR bytes is presented to a member of
the \fBexec\fR family of functions (see \fBexec\fR(2)). The argument list limit
is the sum of the size of the argument list plus the size of the environment's
exported shell variables.
.RE

.sp
.ne 2
.na
\fB8 ENOEXEC\fR
.ad
.RS 23n
Exec format error
.sp
A request is made to execute a file which, although it has the appropriate
permissions, does not start with a valid format (see \fBa.out\fR(5)).
.RE

.sp
.ne 2
.na
\fB9 EBADF\fR
.ad
.RS 23n
Bad file number
.sp
Either a file descriptor refers to no open file, or a \fBread\fR(2)
(respectively,  \fBwrite\fR(2)) request is made to a file that is open only for
writing (respectively, reading).
.RE

.sp
.ne 2
.na
\fB10 ECHILD\fR
.ad
.RS 23n
No child processes
.sp
A \fBwait\fR(3C) function call was executed by a process that had no existing
or unwaited-for child processes.
.RE

.sp
.ne 2
.na
\fB11 EAGAIN\fR
.ad
.RS 23n
No more processes, or no more LWPs
.sp
For example, the \fBfork\fR(2) function failed because the system's process
table is full or the user is not allowed to create any more processes, or a
call failed because of insufficient memory or swap space.
.RE

.sp
.ne 2
.na
\fB12 ENOMEM\fR
.ad
.RS 23n
Not enough space
.sp
During execution of \fBbrk()\fR or \fBsbrk()\fR (see \fBbrk\fR(2)), or one of
the \fBexec\fR family of functions, a program asks for more space than the
system is able to supply. This is not a temporary 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 \fBfork\fR(2)
function.
.RE

.sp
.ne 2
.na
\fB13 EACCES\fR
.ad
.RS 23n
Permission denied
.sp
An attempt was made to access a file in a way forbidden by the protection
system.
.sp
The manual pages for individual functions document which privileges are needed
to override the protection system.
.RE

.sp
.ne 2
.na
\fB14 EFAULT\fR
.ad
.RS 23n
Bad address
.sp
The system encountered a hardware fault in attempting to use an argument of a
routine. For example, \fBerrno\fR potentially may be set to  \fBEFAULT\fR any
time a routine that takes a pointer argument is passed an invalid address, if
the system can detect the condition. Because systems will 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.
.RE

.sp
.ne 2
.na
\fB15 ENOTBLK\fR
.ad
.RS 23n
Block device required
.sp
A non-block device or file was mentioned where a block device was required (for
example, in a call to the \fBmount\fR(2) function).
.RE

.sp
.ne 2
.na
\fB16 EBUSY\fR
.ad
.RS 23n
Device busy
.sp
An attempt was made to mount a device that was already mounted or an attempt
was made to unmount a device on which there is an active file (open file,
current directory, mounted-on file, active text segment). It will also occur if
an attempt is made to enable accounting when it is already enabled. The device
or resource is currently unavailable.   \fBEBUSY\fR is also used by mutexes,
semaphores, condition variables, and r/w locks, to indicate that  a lock is
held,  and by the processor control function  \fBP_ONLINE\fR.
.RE

.sp
.ne 2
.na
\fB17 EEXIST\fR
.ad
.RS 23n
File exists
.sp
An existing file was mentioned in an inappropriate context (for example, call
to the \fBlink\fR(2) function).
.RE

.sp
.ne 2
.na
\fB18 EXDEV\fR
.ad
.RS 23n
Cross-device link
.sp
A hard link to a file on another device was attempted.
.RE

.sp
.ne 2
.na
\fB19 ENODEV\fR
.ad
.RS 23n
No such device
.sp
An attempt was made to apply an inappropriate operation to a device (for
example, read a write-only device).
.RE

.sp
.ne 2
.na
\fB20 ENOTDIR\fR
.ad
.RS 23n
Not a directory
.sp
A non-directory was specified where a directory is required (for example, in a
path prefix or as an argument to the \fBchdir\fR(2) function).
.RE

.sp
.ne 2
.na
\fB21 EISDIR\fR
.ad
.RS 23n
Is a directory
.sp
An attempt was made to write on a directory.
.RE

.sp
.ne 2
.na
\fB22 EINVAL\fR
.ad
.RS 23n
Invalid argument
.sp
An invalid argument was specified (for example, unmounting a non-mounted
device), mentioning an undefined signal in a call to the \fBsignal\fR(3C) or
\fBkill\fR(2) function, or an unsupported operation related to extended
attributes was attempted.
.RE

.sp
.ne 2
.na
\fB23 ENFILE\fR
.ad
.RS 23n
File table overflow
.sp
The system file table is full (that is,  \fBSYS_OPEN\fR files are open, and
temporarily no more files can be opened).
.RE

.sp
.ne 2
.na
\fB24 EMFILE\fR
.ad
.RS 23n
Too many open files
.sp
No process may have more than  \fBOPEN_MAX\fR file descriptors open at a time.
.RE

.sp
.ne 2
.na
\fB25 ENOTTY\fR
.ad
.RS 23n
Inappropriate ioctl for device
.sp
A call was made to the \fBioctl\fR(2) function specifying a file that is not a
special character device.
.RE

.sp
.ne 2
.na
\fB26 ETXTBSY\fR
.ad
.RS 23n
Text file busy (obsolete)
.sp
An attempt was made to execute a pure-procedure program that is currently open
for writing. Also an attempt to open for writing or to remove a pure-procedure
program that is being executed. \fB(This message is obsolete.)\fR
.RE

.sp
.ne 2
.na
\fB27 EFBIG\fR
.ad
.RS 23n
File too large
.sp
The size of the file exceeded the limit specified by resource
\fBRLIMIT_FSIZEn\fR; the file size exceeds the maximum supported by the file
system; or the file size exceeds the offset maximum of the file descriptor.
See the \fBFile Descriptor\fR subsection of the \fBDEFINITIONS\fR section
below.
.RE

.sp
.ne 2
.na
\fB28 ENOSPC\fR
.ad
.RS 23n
No space left on device
.sp
While writing an ordinary file or creating a directory entry, there is no free
space left on the device. In the \fBfcntl\fR(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.
.RE

.sp
.ne 2
.na
\fB29 ESPIPE\fR
.ad
.RS 23n
Illegal seek
.sp
A call to the  \fBlseek\fR(2) function was issued to a pipe.
.RE

.sp
.ne 2
.na
\fB30 EROFS\fR
.ad
.RS 23n
Read-only file system
.sp
An attempt to modify a file or directory was made on a device mounted
read-only.
.RE

.sp
.ne 2
.na
\fB31 EMLINK\fR
.ad
.RS 23n
Too many links
.sp
An attempt to make more than the maximum number of links,  \fBLINK_MAX\fR, to a
file.
.RE

.sp
.ne 2
.na
\fB32 EPIPE\fR
.ad
.RS 23n
Broken pipe
.sp
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.
.RE

.sp
.ne 2
.na
\fB33 EDOM\fR
.ad
.RS 23n
Math argument out of domain of function
.sp
The argument of a function in the math package (3M) is out of the domain of the
function.
.RE

.sp
.ne 2
.na
\fB34 ERANGE\fR
.ad
.RS 23n
Math result not representable
.sp
The value of a function in the math package (3M) is not representable within
machine precision.
.RE

.sp
.ne 2
.na
\fB35 ENOMSG\fR
.ad
.RS 23n
No message of desired type
.sp
An attempt was made to receive a message of a type that does not exist on the
specified message queue (see \fBmsgrcv\fR(2)).
.RE

.sp
.ne 2
.na
\fB36 EIDRM\fR
.ad
.RS 23n
Identifier removed
.sp
This error is returned to processes that resume execution due to the removal of
an identifier from the file system's name space (see \fBmsgctl\fR(2),
\fBsemctl\fR(2), and \fBshmctl\fR(2)).
.RE

.sp
.ne 2
.na
\fB37 ECHRNG\fR
.ad
.RS 23n
Channel number out of range
.RE

.sp
.ne 2
.na
\fB38 EL2NSYNC\fR
.ad
.RS 23n
Level 2 not synchronized
.RE

.sp
.ne 2
.na
\fB39 EL3HLT\fR
.ad
.RS 23n
Level 3 halted
.RE

.sp
.ne 2
.na
\fB40 EL3RST\fR
.ad
.RS 23n
Level 3 reset
.RE

.sp
.ne 2
.na
\fB41 ELNRNG\fR
.ad
.RS 23n
Link number out of range
.RE

.sp
.ne 2
.na
\fB42 EUNATCH\fR
.ad
.RS 23n
Protocol driver not attached
.RE

.sp
.ne 2
.na
\fB43 ENOCSI\fR
.ad
.RS 23n
No CSI structure available
.RE

.sp
.ne 2
.na
\fB44 EL2HLT\fR
.ad
.RS 23n
Level 2 halted
.RE

.sp
.ne 2
.na
\fB45 EDEADLK\fR
.ad
.RS 23n
Deadlock condition
.sp
A deadlock situation was detected and avoided. This error pertains to file and
record locking, and also applies to mutexes, semaphores, condition variables,
and r/w locks.
.RE

.sp
.ne 2
.na
\fB46 ENOLCK\fR
.ad
.RS 23n
No record locks available
.sp
There are no more locks available. The system lock table is full (see
\fBfcntl\fR(2)).
.RE

.sp
.ne 2
.na
\fB47 ECANCELED\fR
.ad
.RS 23n
Operation canceled
.sp
The associated asynchronous operation was canceled before completion.
.RE

.sp
.ne 2
.na
\fB48 ENOTSUP\fR
.ad
.RS 23n
Not supported
.sp
This version of the system does not support this feature. Future versions of
the system may provide support.
.RE

.sp
.ne 2
.na
\fB49 EDQUOT\fR
.ad
.RS 23n
Disc quota exceeded
.sp
A \fBwrite\fR(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 allocation of an inode for a newly created
file failed because the user's quota of inodes was exhausted.
.RE

.sp
.ne 2
.na
\fB58-59\fR
.ad
.RS 23n
Reserved
.RE

.sp
.ne 2
.na
\fB60 ENOSTR\fR
.ad
.RS 23n
Device not a stream
.sp
A \fBputmsg\fR(2) or \fBgetmsg\fR(2) call was attempted on a file descriptor
that is not a STREAMS device.
.RE

.sp
.ne 2
.na
\fB61 ENODATA\fR
.ad
.RS 23n
No data available
.RE

.sp
.ne 2
.na
\fB62 ETIME\fR
.ad
.RS 23n
Timer expired
.sp
The timer set for a STREAMS \fBioctl\fR(2) call has expired. The cause of this
error is device-specific and could indicate either a hardware or software
failure, or perhaps a timeout value that is too short for the specific
operation. The status of the \fBioctl()\fR operation is indeterminate. This is
also returned in the case of \fB_lwp_cond_timedwait\fR(2) or
\fBcond_timedwait\fR(3C).
.RE

.sp
.ne 2
.na
\fB63 ENOSR\fR
.ad
.RS 23n
Out of stream resources
.sp
During a  \fBSTREAMS\fR \fBopen\fR(2) call, either no  \fBSTREAMS\fR queues or
no \fBSTREAMS\fR head data structures were available. This is a temporary
condition; one may recover from it if other processes release resources.
.RE

.sp
.ne 2
.na
\fB65 ENOPKG\fR
.ad
.RS 23n
Package not installed
.sp
This error occurs when users attempt to use a call from a package which has not
been installed.
.RE

.sp
.ne 2
.na
\fB71 EPROTO\fR
.ad
.RS 23n
Protocol error
.sp
Some protocol error occurred.  This error is device-specific, but is generally
not related to a hardware failure.
.RE

.sp
.ne 2
.na
\fB77 EBADMSG\fR
.ad
.RS 23n
Not a data message
.sp
During a \fBread\fR(2), \fBgetmsg\fR(2), or \fBioctl\fR(2) \fBI_RECVFD\fR call
to a STREAMS device, something has come to the head of the queue that can not
be processed.  That something depends on the call:
.sp
.ne 2
.na
\fB\fBread()\fR:\fR
.ad
.RS 13n
control information or passed file descriptor.
.RE

.sp
.ne 2
.na
\fB\fBgetmsg()\fR:\fR
.ad
.RS 13n
passed file descriptor.
.RE

.sp
.ne 2
.na
\fB\fBioctl()\fR:\fR
.ad
.RS 13n
control or data information.
.RE

.RE

.sp
.ne 2
.na
\fB78 ENAMETOOLONG\fR
.ad
.RS 23n
File name too long
.sp
The length of the path argument exceeds  \fIPATH_MAX\fR, or the length of a
path component exceeds \fINAME_MAX\fR while \fB_POSIX_NO_TRUNC\fR is in effect;
see \fBlimits.h\fR(3HEAD).
.RE

.sp
.ne 2
.na
\fB79 EOVERFLOW\fR
.ad
.RS 23n
Value too large for defined data type.
.RE

.sp
.ne 2
.na
\fB80 ENOTUNIQ\fR
.ad
.RS 23n
Name not unique on network
.sp
Given log name not unique.
.RE

.sp
.ne 2
.na
\fB81 EBADFD\fR
.ad
.RS 23n
File descriptor in bad state
.sp
Either a file descriptor refers to no open file or a read request was made to a
file that is open only for writing.
.RE

.sp
.ne 2
.na
\fB82 EREMCHG\fR
.ad
.RS 23n
Remote address changed
.RE

.sp
.ne 2
.na
\fB83 ELIBACC\fR
.ad
.RS 23n
Cannot access a needed share library
.sp
Trying to \fBexec\fR an \fBa.out\fR that requires a static shared library and
the static shared library does not exist or the user does not have permission
to use it.
.RE

.sp
.ne 2
.na
\fB84 ELIBBAD\fR
.ad
.RS 23n
Accessing a corrupted shared library
.sp
Trying to \fBexec\fR an \fBa.out\fR that requires a static shared library (to
be linked in) and \fBexec\fR could not load the static shared library. The
static shared library is probably corrupted.
.RE

.sp
.ne 2
.na
\fB85 ELIBSCN\fR
.ad
.RS 23n
\fB\&.lib\fR section in \fBa.out\fR corrupted
.sp
Trying to \fBexec\fR an \fBa.out\fR that requires a static shared library (to
be linked in) and there was erroneous data in the \fB\&.lib\fR section of the
\fBa.out\fR. The \fB\&.lib\fR section tells \fBexec\fR what static shared
libraries are needed. The \fBa.out\fR is probably corrupted.
.RE

.sp
.ne 2
.na
\fB86 ELIBMAX\fR
.ad
.RS 23n
Attempting to link in more shared libraries than system limit
.sp
Trying to \fBexec\fR an \fBa.out\fR that requires more static shared libraries
than is allowed on the current configuration of the system. See \fISystem
Administration Guide: IP Services\fR
.RE

.sp
.ne 2
.na
\fB87 ELIBEXEC\fR
.ad
.RS 23n
Cannot \fBexec\fR a shared library directly
.sp
Attempting to \fBexec\fR a shared library directly.
.RE

.sp
.ne 2
.na
\fB88 EILSEQ\fR
.ad
.RS 23n
Error 88
.sp
Illegal byte sequence. Handle multiple characters as a single character.
.RE

.sp
.ne 2
.na
\fB89 ENOSYS\fR
.ad
.RS 23n
Operation not applicable
.RE

.sp
.ne 2
.na
\fB90 ELOOP\fR
.ad
.RS 23n
Number of symbolic links encountered during path name traversal exceeds
\fBMAXSYMLINKS\fR
.RE

.sp
.ne 2
.na
\fB91 ESTART\fR
.ad
.RS 23n
Restartable system call
.sp
Interrupted system call should be restarted.
.RE

.sp
.ne 2
.na
\fB92 ESTRPIPE\fR
.ad
.RS 23n
If pipe/FIFO, don't sleep in stream head
.sp
Streams pipe error (not externally visible).
.RE

.sp
.ne 2
.na
\fB93 ENOTEMPTY\fR
.ad
.RS 23n
Directory not empty
.RE

.sp
.ne 2
.na
\fB94 EUSERS\fR
.ad
.RS 23n
Too many users
.RE

.sp
.ne 2
.na
\fB95 ENOTSOCK\fR
.ad
.RS 23n
Socket operation on non-socket
.RE

.sp
.ne 2
.na
\fB96 EDESTADDRREQ\fR
.ad
.RS 23n
Destination address required
.sp
A required address was omitted from an operation on a transport endpoint.
Destination address required.
.RE

.sp
.ne 2
.na
\fB97 EMGSIZE\fR
.ad
.RS 23n
Message too long
.sp
A message sent on a transport provider was larger than the internal message
buffer or some other network limit.
.RE

.sp
.ne 2
.na
\fB98 EPROTOTYPE\fR
.ad
.RS 23n
Protocol wrong type for socket
.sp
A protocol was specified that does not support the semantics of the socket type
requested.
.RE

.sp
.ne 2
.na
\fB99 ENOPROTOOPT\fR
.ad
.RS 23n
Protocol not available
.sp
A bad option or level was specified when getting or setting options for a
protocol.
.RE

.sp
.ne 2
.na
\fB120 EPROTONOSUPPORT\fR
.ad
.RS 23n
Protocol not supported
.sp
The protocol has not been configured into the system or no implementation for
it exists.
.RE

.sp
.ne 2
.na
\fB121 ESOCKTNOSUPPORT\fR
.ad
.RS 23n
Socket type not supported
.sp
The support for the socket type has not been configured into the system or no
implementation for it exists.
.RE

.sp
.ne 2
.na
\fB122 EOPNOTSUPP\fR
.ad
.RS 23n
Operation not supported on transport endpoint
.sp
For example, trying to accept a connection on a datagram transport endpoint.
.RE

.sp
.ne 2
.na
\fB123 EPFNOSUPPORT\fR
.ad
.RS 23n
Protocol family not supported
.sp
The protocol family has not been configured into the system or no
implementation for it exists. Used for the Internet protocols.
.RE

.sp
.ne 2
.na
\fB124 EAFNOSUPPORT\fR
.ad
.RS 23n
Address family not supported by protocol family
.sp
An address incompatible with the requested protocol was used.
.RE

.sp
.ne 2
.na
\fB125 EADDRINUSE\fR
.ad
.RS 23n
Address already in use
.sp
User attempted to use an address already in use, and the protocol does not
allow this.
.RE

.sp
.ne 2
.na
\fB126 EADDRNOTAVAIL\fR
.ad
.RS 23n
Cannot assign requested address
.sp
Results from an attempt to create a transport endpoint with an address not on
the current machine.
.RE

.sp
.ne 2
.na
\fB127 ENETDOWN\fR
.ad
.RS 23n
Network is down
.sp
Operation encountered a dead network.
.RE

.sp
.ne 2
.na
\fB128 ENETUNREACH\fR
.ad
.RS 23n
Network is unreachable
.sp
Operation was attempted to an unreachable network.
.RE

.sp
.ne 2
.na
\fB129 ENETRESET\fR
.ad
.RS 23n
Network dropped connection because of reset
.sp
The host you were connected to crashed and rebooted.
.RE

.sp
.ne 2
.na
\fB130 ECONNABORTED\fR
.ad
.RS 23n
Software caused connection abort
.sp
A connection abort was caused internal to your host machine.
.RE

.sp
.ne 2
.na
\fB131 ECONNRESET\fR
.ad
.RS 23n
Connection reset by peer
.sp
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.
.RE

.sp
.ne 2
.na
\fB132 ENOBUFS\fR
.ad
.RS 23n
No buffer space available
.sp
An operation on a transport endpoint or pipe was not performed because the
system lacked sufficient buffer space or because a queue was full.
.RE

.sp
.ne 2
.na
\fB133 EISCONN\fR
.ad
.RS 23n
Transport endpoint is already connected
.sp
A connect request was made on an already connected transport endpoint; or, a
\fBsendto\fR(3SOCKET) or \fBsendmsg\fR(3SOCKET) request on a connected
transport endpoint specified a destination when already connected.
.RE

.sp
.ne 2
.na
\fB134 ENOTCONN\fR
.ad
.RS 23n
Transport endpoint is not connected
.sp
A request to send or receive data was disallowed because the transport endpoint
is not connected and (when sending a datagram) no address was supplied.
.RE

.sp
.ne 2
.na
\fB143 ESHUTDOWN\fR
.ad
.RS 23n
Cannot send after transport endpoint shutdown
.sp
A request to send data was disallowed because the transport endpoint has
already been shut down.
.RE

.sp
.ne 2
.na
\fB144 ETOOMANYREFS\fR
.ad
.RS 23n
Too many references: cannot splice
.RE

.sp
.ne 2
.na
\fB145 ETIMEDOUT\fR
.ad
.RS 23n
Connection timed out
.sp
A  \fBconnect\fR(3SOCKET) or  \fBsend\fR(3SOCKET) request failed because the
connected party did not properly respond after a period of time; or a
\fBwrite\fR(2) or  \fBfsync\fR(3C) request failed because a file is on an
\fBNFS\fR file system mounted with the  \fIsoft\fR option.
.RE

.sp
.ne 2
.na
\fB146 ECONNREFUSED\fR
.ad
.RS 23n
Connection refused
.sp
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.
.RE

.sp
.ne 2
.na
\fB147 EHOSTDOWN\fR
.ad
.RS 23n
Host is down
.sp
A transport provider operation failed because the destination host was down.
.RE

.sp
.ne 2
.na
\fB148 EHOSTUNREACH\fR
.ad
.RS 23n
No route to host
.sp
A transport provider operation was attempted to an unreachable host.
.RE

.sp
.ne 2
.na
\fB149 EALREADY\fR
.ad
.RS 23n
Operation already in progress
.sp
An operation was attempted on a non-blocking object that already had an
operation in progress.
.RE

.sp
.ne 2
.na
\fB150 EINPROGRESS\fR
.ad
.RS 23n
Operation now in progress
.sp
An operation that takes a long time to complete (such as a \fBconnect()\fR) was
attempted on a non-blocking object.
.RE

.sp
.ne 2
.na
\fB151 ESTALE\fR
.ad
.RS 23n
Stale NFS file handle
.RE

.SH DEFINITIONS
.SS "Background Process Group"
.sp
.LP
Any process group that is not the foreground process group  of a session that
has established a connection with a controlling terminal.
.SS "Controlling Process"
.sp
.LP
A session leader that established a connection to a controlling terminal.
.SS "Controlling Terminal"
.sp
.LP
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; see \fBtermio\fR(4I).
.SS "Directory"
.sp
.LP
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, \fB\&.\fR (dot) and \fB\&..\fR (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 \fB/\fR and the parent
directory of the root directory is \fB/\fR.
.SS "Downstream"
.sp
.LP
In a stream, the direction from stream head to driver.
.SS "Driver"
.sp
.LP
In a stream, the driver provides the interface between peripheral hardware and
the stream. A driver can also be a pseudo-driver, such as a multiplexor or log
driver (see \fBlog\fR(4D)), which is not associated with a hardware device.
.SS "Effective User \fBID\fR and Effective Group \fBID\fR"
.sp
.LP
An active process has an effective user \fBID\fR and an effective group
\fBID\fR that are used to determine file access permissions (see below). The
effective user \fBID\fR and effective group \fBID\fR are equal to the process's
real user \fBID\fR and real group \fBID,\fR 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 \fBexec\fR(2)).
.SS "File Access Permissions"
.sp
.LP
Read, write, and execute/search permissions for a file are granted to a process
if one or more of the following are true:
.RS +4
.TP
.ie t \(bu
.el 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.
.RE
.RS +4
.TP
.ie t \(bu
.el 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.
.RE
.RS +4
.TP
.ie t \(bu
.el 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.
.RE
.RS +4
.TP
.ie t \(bu
.el 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:
{\fBPRIV_FILE_DAC_READ\fR} for the read bit {\fBPRIV_FILE_DAC_WRITE\fR} for the
write bit, {\fBPRIV_FILE_DAC_SEARCH\fR} for the execute bit on directories, and
{\fBPRIV_FILE_DAC_EXECUTE\fR} for the executable bit on plain files.
.RE
.sp
.LP
Otherwise, the corresponding permissions are denied.
.SS "File Descriptor"
.sp
.LP
A file descriptor is a small integer used to perform \fBI/O\fR on a file. The
value of a file descriptor is from \fB0\fR to (\fBNOFILES\(mi1\fR). A process
may have no more than  \fBNOFILES\fR file descriptors  open simultaneously. A
file descriptor is returned by calls such as \fBopen\fR(2) or \fBpipe\fR(2).
The file descriptor is used as an argument by calls such as \fBread\fR(2),
\fBwrite\fR(2), \fBioctl\fR(2), and \fBclose\fR(2).
.sp
.LP
Each file descriptor has a corresponding offset maximum. For regular files that
were opened without setting the \fBO_LARGEFILE\fR flag, the offset maximum is 2
Gbyte \(mi 1 byte (2^31 \(mi1 bytes). For regular files that were opened with
the \fBO_LARGEFILE\fR flag set, the offset maximum is 2^63 \(mi1 bytes.
.SS "File Name"
.sp
.LP
Names consisting of 1 to  \fINAME_MAX\fR characters may be used to name an
ordinary file, special file or directory.
.sp
.LP
These characters may be selected from the set of all character values excluding
\e0 (null) and the \fBASCII\fR code for \fB/\fR (slash).
.sp
.LP
Note that it is generally unwise to use \fB*\fR, \fB?\fR, \fB[\fR, or \fB]\fR
as part of file names because of the special meaning attached to these
characters by the shell (see \fBsh\fR(1), \fBcsh\fR(1), and \fBksh\fR(1)).
Although permitted, the use of unprintable characters in file names should be
avoided.
.sp
.LP
A file name is sometimes referred to as a pathname component.  The
interpretation of a pathname component is dependent on the values of
\fINAME_MAX\fR and  \fB_POSIX_NO_TRUNC\fR associated with the path prefix of
that component.  If any pathname component is longer than \fINAME_MAX\fR and
\fB_POSIX_NO_TRUNC\fR is in effect for the path prefix of that component (see
\fBfpathconf\fR(2) and \fBlimits.h\fR(3HEAD)), it shall be considered an error
condition in  that implementation. Otherwise, the implementation shall use the
first \fINAME_MAX\fR bytes of the pathname component.
.SS "Foreground Process Group"
.sp
.LP
Each session that has established a connection with a controlling terminal will
distinguish one process group of the session as the foreground process group of
the controlling terminal.  This group has certain privileges when accessing its
controlling terminal that are denied to background process groups.
.SS "{IOV_MAX}"
.sp
.LP
Maximum number of entries in a \fBstruct iovec\fR array.
.SS "{LIMIT}"
.sp
.LP
The braces notation, \fB{LIMIT}\fR, 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 \fBpathconf\fR(2) with the name
argument  \fB_PC_LIMIT\fR.
.SS "Masks"
.sp
.LP
The file mode creation mask of the process used during any create function
calls to turn off permission bits in the \fImode\fR argument supplied. Bit
positions that are set in \fBumask(\fR\fIcmask\fR\fB)\fR are cleared in the
mode of the created file.
.SS "Message"
.sp
.LP
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.
.SS "Message Queue"
.sp
.LP
In a stream, a linked list of messages awaiting processing by a module or
driver.
.SS "Message Queue Identifier"
.sp
.LP
A message queue identifier (\fBmsqid\fR) is a unique positive integer created
by a \fBmsgget\fR(2) call. Each \fBmsqid\fR has a message queue and a data
structure associated with it. The data structure is referred to as
\fBmsqid_ds\fR and contains the following members:
.sp
.in +2
.nf
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;
.fi
.in -2

.sp
.LP
The following are descriptions of the \fBmsqid_ds\fR structure members:
.sp
.LP
The \fBmsg_perm\fR member is an \fBipc_perm\fR structure that specifies the
message operation permission (see below). This structure includes the following
members:
.sp
.in +2
.nf
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 */
.fi
.in -2

.sp
.LP
The \fB*msg_first\fR member is a pointer to the first message on the queue.
.sp
.LP
The \fB*msg_last\fR member is a pointer to the last message on the queue.
.sp
.LP
The \fBmsg_cbytes\fR member is the current number of bytes on the queue.
.sp
.LP
The \fBmsg_qnum\fR member is the number of messages currently on the queue.
.sp
.LP
The \fBmsg_qbytes\fR member is the maximum number of bytes allowed on the
queue.
.sp
.LP
The \fBmsg_lspid\fR member is the process \fBID\fR of the last process that
performed a \fBmsgsnd()\fR operation.
.sp
.LP
The \fBmsg_lrpid\fR member is the process id of the last process that performed
a \fBmsgrcv()\fR operation.
.sp
.LP
The \fBmsg_stime\fR member is the time of the last \fBmsgsnd()\fR operation.
.sp
.LP
The \fBmsg_rtime\fR member is the time of the last \fBmsgrcv()\fR operation.
.sp
.LP
The \fBmsg_ctime\fR member is the time of the last \fBmsgctl()\fR operation
that changed a member of the above structure.
.SS "Message Operation Permissions"
.sp
.LP
In the \fBmsgctl\fR(2), \fBmsgget\fR(2), \fBmsgrcv\fR(2), and \fBmsgsnd\fR(2)
function descriptions, the permission required for an operation is given as
{\fItoken\fR}, where \fItoken\fR is the type of permission needed, interpreted
as follows:
.sp
.in +2
.nf
00400   READ by user
00200   WRITE by user
00040   READ by group
00020   WRITE by group
00004   READ by others
00002   WRITE by others
.fi
.in -2

.sp
.LP
Read and write permissions for a \fBmsqid\fR are granted to a process if one or
more of the following are true:
.RS +4
.TP
.ie t \(bu
.el o
The {\fBPRIV_IPC_DAC_READ\fR} or {\fBPRIV_IPC_DAC_WRITE\fR} privilege is
present in the effective set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The effective user \fBID\fR of the process matches \fBmsg_perm.cuid\fR or
\fBmsg_perm.uid\fR in the data structure associated with \fBmsqid\fR and the
appropriate bit of the "user" portion (0600) of \fBmsg_perm.mode\fR is set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
Any group ID in the process credentials from the set (\fBcr_gid\fR,
\fBcr_groups\fR) matches \fBmsg_perm.cgid\fR or \fBmsg_perm.gid\fR and the
appropriate bit of the "group" portion (060) of \fBmsg_perm.mode\fR is set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The appropriate bit of the "other" portion (006) of \fBmsg_perm.mode\fR is
set."
.RE
.sp
.LP
Otherwise, the corresponding permissions are denied.
.SS "Module"
.sp
.LP
A module is an entity containing processing routines for input and output 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.
.SS "Multiplexor"
.sp
.LP
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 constructing them and
for connecting multiplexed configurations of streams.
.SS "Offset Maximum"
.sp
.LP
An offset maximum is an attribute of an open file description representing the
largest value that can be used as a file offset.
.SS "Orphaned Process Group"
.sp
.LP
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.
.SS "Path Name"
.sp
.LP
A path name is a null-terminated character string starting with an optional
slash (\fB/\fR), followed by zero or more directory names separated by slashes,
optionally followed by a file name.
.sp
.LP
If a path name begins with a slash, the path search begins at the root
directory. Otherwise, the search begins from the current working directory.
.sp
.LP
A slash by itself names the root directory.
.sp
.LP
Unless specifically stated otherwise, the null path name is treated as if it
named a non-existent file.
.SS "Privileged User"
.sp
.LP
Solaris software implements a set of privileges that provide fine-grained
control over the actions of processes. The possession of of a certain privilege
allows a process to perform a specific set of restricted operations. Prior to
the Solaris 10 release, a process running with uid 0 was granted all
privileges. See \fBprivileges\fR(7) for the semantics and the degree of
backward compatibility awarded to processes with an effective uid of 0.
.SS "Process \fBID\fR"
.sp
.LP
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 lifetime, 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 \fBthread_t\fR and
\fBLWPID_t\fR. These threads are not visible to the outside process.
.SS "Parent Process \fBID\fR"
.sp
.LP
A new process is created by a currently active process (see \fBfork\fR(2)). The
parent process \fBID\fR of a process is the process \fBID\fR of its creator.
.SS "Privilege"
.sp
.LP
Having appropriate privilege means having the capability to override system
restrictions.
.SS "Process Group"
.sp
.LP
Each process in the system is a member of a process group that is identified 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.
.SS "Process Group Leader"
.sp
.LP
A process group leader is a process whose process \fBID\fR is the same as its
process group ID.
.SS "Process Group \fBID\fR"
.sp
.LP
Each active process is a member of a process group and is identified by a
positive integer called the process group ID. This \fBID\fR is the process
\fBID\fR of the group leader. This grouping permits the signaling of related
processes (see \fBkill\fR(2)).
.SS "Process Lifetime"
.sp
.LP
A process lifetime begins when the process is forked and ends after it exits,
when its termination has been acknowledged by its parent process. See
\fBwait\fR(3C).
.SS "Process Group Lifetime"
.sp
.LP
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.
.SS "Processor Set \fBID\fR"
.sp
.LP
The processors in a system may be divided into subsets, known as processor
sets. A process bound to one of these sets will run only on processors 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. See \fBpset_create\fR(2).
.SS "Read Queue"
.sp
.LP
In a stream, the message queue in a module or driver containing messages moving
upstream.
.SS "Real User \fBID\fR and Real Group \fBID\fR"
.sp
.LP
Each user allowed on the system is  identified by a positive integer (\fB0\fR
to  \fBMAXUID\fR) called a real user \fBID.\fR
.sp
.LP
Each user is also a member of a group. The group is identified by a positive
integer called the real group \fBID.\fR
.sp
.LP
An active process has a real user \fBID\fR and real group \fBID\fR that are set
to the real user \fBID\fR and real group \fBID,\fR respectively, of the user
responsible for the creation of the process.
.SS "Root Directory and Current Working Directory"
.sp
.LP
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 directory of the root file system.
.SS "Saved Resource Limits"
.sp
.LP
Saved resource limits is an attribute of a process that provides some
flexibility in the handling of unrepresentable resource limits, as described in
the \fBexec\fR family of functions and \fBsetrlimit\fR(2).
.SS "Saved User \fBID\fR and Saved Group \fBID\fR"
.sp
.LP
The saved user \fBID\fR and saved group \fBID\fR are the values of the
effective user \fBID\fR and effective group \fBID\fR just after an \fBexec\fR
of a file whose set user or set group file mode bit has been set (see
\fBexec\fR(2)).
.SS "Semaphore Identifier"
.sp
.LP
A semaphore identifier (\fBsemid\fR) is a unique positive  integer created by a
\fBsemget\fR(2) call. Each \fBsemid\fR has a set of semaphores and a data
structure associated with it. The data structure is referred to as
\fBsemid_ds\fR and contains the following members:
.sp
.in +2
.nf
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 */
.fi
.in -2

.sp
.LP
The following are descriptions of the \fBsemid_ds\fR structure members:
.sp
.LP
The \fBsem_perm\fR member is an \fBipc_perm\fR structure that specifies the
semaphore operation permission (see below). This structure includes the
following members:
.sp
.in +2
.nf
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 */
.fi
.in -2

.sp
.LP
The \fBsem_nsems\fR 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 \fBsem_num\fR. \fBsem_num\fR values run sequentially from \fB0\fR to the
value of \fBsem_nsems\fR minus 1.
.sp
.LP
The \fBsem_otime\fR member is the time of the last \fBsemop\fR(2) operation.
.sp
.LP
The \fBsem_ctime\fR member is the time of the last \fBsemctl\fR(2) operation
that changed a member of the above structure.
.sp
.LP
A semaphore is a data structure called \fBsem\fR that contains the following
members:
.sp
.in +2
.nf
ushort_t   semval;    /* semaphore value */
pid_t      sempid;    /* pid of last operation  */
ushort_t   semncnt;   /* # awaiting semval > cval */
ushort_t   semzcnt;   /* # awaiting semval = 0 */
.fi
.in -2

.sp
.LP
The following are descriptions of the \fBsem\fR structure members:
.sp
.LP
The \fBsemval\fR member is a non-negative integer that is the actual value of
the semaphore.
.sp
.LP
The \fBsempid\fR member is equal to the process \fBID\fR of the last process
that performed a semaphore operation on this semaphore.
.sp
.LP
The \fBsemncnt\fR member is a count of the number of processes that are
currently suspended awaiting this semaphore's \fBsemval\fR to become greater
than its current value.
.sp
.LP
The \fBsemzcnt\fR member is a count of the number of processes that are
currently suspended awaiting this semaphore's \fBsemval\fR to become \fB0\fR.
.SS "Semaphore Operation Permissions"
.sp
.LP
In the \fBsemop\fR(2) and \fBsemctl\fR(2) function descriptions, the permission
required for an operation is given as {\fItoken\fR}, where \fItoken\fR is the
type of permission needed interpreted as follows:
.sp
.in +2
.nf
\fB00400	  READ by user
00200   ALTER by user
00040   READ by group
00020   ALTER by group
00004   READ by others
00002   ALTER by others\fR
.fi
.in -2

.sp
.LP
Read and alter permissions for a \fBsemid\fR are granted to a process if one or
more of the following are true:
.RS +4
.TP
.ie t \(bu
.el o
The {\fBPRIV_IPC_DAC_READ\fR} or {\fBPRIV_IPC_DAC_WRITE\fR} privilege is
present in the effective set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The effective user \fBID\fR of the process matches \fBsem_perm.cuid\fR or
\fBsem_perm.uid\fR in the data structure associated with \fBsemid\fR and the
appropriate bit of the "user" portion (0600) of \fBsem_perm.mode\fR is set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The effective group \fBID\fR of the process matches \fBsem_perm.cgid\fR or
\fBsem_perm.gid\fR and the appropriate bit of the "group" portion (060) of
\fBsem_perm.mode\fR is set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The appropriate bit of the "other" portion (06) of \fBsem_perm.mode\fR is set.
.RE
.sp
.LP
Otherwise, the corresponding permissions are denied.
.SS "Session"
.sp
.LP
A session is a group of processes identified by a common \fBID\fR 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 session and process group
leader of the process group.  A newly created process joins the session of its
creator.
.SS "Session \fBID\fR"
.sp
.LP
Each session in the system is uniquely identified during its lifetime by  a
positive integer called a session ID, the process \fBID\fR of its session
leader.
.SS "Session Leader"
.sp
.LP
A session leader is a process whose session \fBID\fR is the same as its
process and process group ID.
.SS "Session Lifetime"
.sp
.LP
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.
.SS "Shared Memory Identifier"
.sp
.LP
A shared memory identifier (\fBshmid\fR) is a unique positive integer created
by a \fBshmget\fR(2) call. Each \fBshmid\fR has a segment of memory (referred
to as a shared memory segment) and a data structure associated with it. (Note
that these shared memory segments must be explicitly removed by the user after
the last reference to them is removed.) The data structure is referred to as
\fBshmid_ds\fR and contains the following members:
.sp
.in +2
.nf
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 */
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 */
.fi
.in -2

.sp
.LP
The following are descriptions of the \fBshmid_ds\fR structure members:
.sp
.LP
The \fBshm_perm\fR member is an \fBipc_perm\fR structure that specifies the
shared memory operation permission (see below). This structure includes the
following members:
.sp
.in +2
.nf
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 */
.fi
.in -2

.sp
.LP
The \fBshm_segsz\fR member specifies the size of the shared memory segment in
bytes.
.sp
.LP
The \fBshm_cpid\fR member is the process \fBID\fR of the process that created
the shared memory identifier.
.sp
.LP
The \fBshm_lpid\fR member is the process \fBID\fR of the last process that
performed a \fBshmat()\fR or \fBshmdt()\fR operation (see \fBshmop\fR(2)).
.sp
.LP
The \fBshm_nattch\fR member is the number of processes that currently have this
segment attached.
.sp
.LP
The \fBshm_atime\fR member is the time of the last \fBshmat()\fR operation (see
\fBshmop\fR(2)).
.sp
.LP
The \fBshm_dtime\fR member is the time of the last \fBshmdt()\fR operation (see
\fBshmop\fR(2)).
.sp
.LP
The \fBshm_ctime\fR member is the time of the last \fBshmctl\fR(2) operation
that changed one of the members of the above structure.
.SS "Shared Memory Operation Permissions"
.sp
.LP
In the \fBshmctl\fR(2), \fBshmat()\fR, and \fBshmdt()\fR (see \fBshmop\fR(2))
function descriptions, the permission required for an operation is given as
{\fItoken\fR}, where \fItoken\fR is the type of permission needed interpreted
as follows:
.sp
.in +2
.nf
00400   READ by user
00200   WRITE by user
00040   READ by group
00020   WRITE by group
00004   READ by others
00002   WRITE by others
.fi
.in -2

.sp
.LP
Read and write permissions for a \fBshmid\fR are granted to a process if one or
more of the following are true:
.RS +4
.TP
.ie t \(bu
.el o
The {\fBPRIV_IPC_DAC_READ\fR} or {\fBPRIV_IPC_DAC_WRITE\fR} privilege is
present in the effective set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The effective user \fBID\fR of the process matches \fBshm_perm.cuid\fR or
\fBshm_perm.uid\fR in the data structure associated with \fBshmid\fR and the
appropriate bit of the "user" portion (0600) of \fBshm_perm.mode\fR is set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The effective group \fBID\fR of the process matches \fBshm_perm.cgid\fR or
\fBshm_perm.gid\fR and the appropriate bit of the "group" portion (060) of
\fBshm_perm.mode\fR is set.
.RE
.RS +4
.TP
.ie t \(bu
.el o
The appropriate bit of the "other" portion (06) of \fBshm_perm.mode\fR is set.
.RE
.sp
.LP
Otherwise, the corresponding permissions are denied.
.SS "Special Processes"
.sp
.LP
The process with \fBID\fR 0 and the process with \fBID\fR 1 are special
processes referred to as proc0 and proc1; see \fBkill\fR(2). proc0 is the
process scheduler. proc1 is the initialization process (\fIinit\fR); proc1 is
the ancestor of every other process in the system and is used to control the
process structure.
.SS "\fBSTREAMS\fR"
.sp
.LP
A set of kernel mechanisms that support the development of network services and
data communication drivers. It defines interface standards for character
input/output 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.
.SS "Stream"
.sp
.LP
A stream is a full-duplex data path within the kernel  between a user process
and driver routines. The primary components 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.
.SS "Stream Head"
.sp
.LP
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 functions of the
stream head are processing STREAMS-related system calls and passing data and
information between a user process and the stream.
.SS "Upstream"
.sp
.LP
In a stream, the direction from driver to stream head.
.SS "Write Queue"
.sp
.LP
In a stream, the message queue in a module or driver containing messages moving
downstream.
.SH ACKNOWLEDGMENTS
.sp
.LP
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to
reproduce portions of its copyrighted documentation. Original documentation
from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/\&.
.sp
.LP
The Institute of Electrical and Electronics Engineers and The Open Group, have
given us permission to reprint portions of their documentation.
.sp
.LP
In the following statement, the phrase ``this text'' refers to portions of the
system documentation.
.sp
.LP
Portions of this text are reprinted and reproduced in electronic form in the
SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for
Information Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of
Electrical and Electronics Engineers, 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
http://www.opengroup.org/unix/online.html\&.
.sp
.LP
This notice shall appear on any product containing this material.
.SH SEE ALSO
.sp
.LP
.BR standards (7),
.BR threads (7)