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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 \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)