NAME
stropts.h - STREAMS interface (STREAMS)
SYNOPSIS
#include <stropts.h>
DESCRIPTION
The <stropts.h> header shall define the bandinfo structure that
includes at least the following members:
unsigned char bi_pri Priority band.
int bi_flag Flushing type.
The <stropts.h> header shall define the strpeek structure that includes
at least the following members:
struct strbuf ctlbuf The control portion of the message.
struct strbuf databuf The data portion of the message.
t_uscalar_t flags RS_HIPRI or 0.
The <stropts.h> header shall define the strbuf structure that includes
at least the following members:
int maxlen Maximum buffer length.
int len Length of data.
char *buf Pointer to buffer.
The <stropts.h> header shall define the strfdinsert structure that
includes at least the following members:
struct strbuf ctlbuf The control portion of the message.
struct strbuf databuf The data portion of the message.
t_uscalar_t flags RS_HIPRI or 0.
int fildes File descriptor of the other STREAM.
int offset Relative location of the stored value.
The <stropts.h> header shall define the strioctl structure that
includes at least the following members:
int ic_cmd ioctl() command.
int ic_timout Timeout for response.
int ic_len Length of data.
char *ic_dp Pointer to buffer.
The <stropts.h> header shall define the strrecvfd structure that
includes at least the following members:
int fda Received file descriptor.
uid_t uid UID of sender.
gid_t gid GID of sender.
The uid_t and gid_t types shall be defined through typedef as described
in <sys/types.h> .
The <stropts.h> header shall define the t_scalar_t and t_uscalar_t
types, respectively, as signed and unsigned opaque types of equal
length of at least 32 bits.
The <stropts.h> header shall define the str_list structure that
includes at least the following members:
int sl_nmods Number of STREAMS module names.
struct str_mlist *sl_modlist STREAMS module names.
The <stropts.h> header shall define the str_mlist structure that
includes at least the following member:
char l_name[FMNAMESZ+1] A STREAMS module name.
At least the following macros shall be defined for use as the request
argument to ioctl():
I_PUSH Push a STREAMS module.
I_POP Pop a STREAMS module.
I_LOOK Get the top module name.
I_FLUSH
Flush a STREAM.
I_FLUSHBAND
Flush one band of a STREAM.
I_SETSIG
Ask for notification signals.
I_GETSIG
Retrieve current notification signals.
I_FIND Look for a STREAMS module.
I_PEEK Peek at the top message on a STREAM.
I_SRDOPT
Set the read mode.
I_GRDOPT
Get the read mode.
I_NREAD
Size the top message.
I_FDINSERT
Send implementation-defined information about another STREAM.
I_STR Send a STREAMS ioctl().
I_SWROPT
Set the write mode.
I_GWROPT
Get the write mode.
I_SENDFD
Pass a file descriptor through a STREAMS pipe.
I_RECVFD
Get a file descriptor sent via I_SENDFD.
I_LIST Get all the module names on a STREAM.
I_ATMARK
Is the top message "marked’’?
I_CKBAND
See if any messages exist in a band.
I_GETBAND
Get the band of the top message on a STREAM.
I_CANPUT
Is a band writable?
I_SETCLTIME
Set close time delay.
I_GETCLTIME
Get close time delay.
I_LINK Connect two STREAMs.
I_UNLINK
Disconnect two STREAMs.
I_PLINK
Persistently connect two STREAMs.
I_PUNLINK
Dismantle a persistent STREAMS link.
At least the following macros shall be defined for use with I_LOOK:
FMNAMESZ
The minimum size in bytes of the buffer referred to by the arg
argument.
At least the following macros shall be defined for use with I_FLUSH:
FLUSHR Flush read queues.
FLUSHW Flush write queues.
FLUSHRW
Flush read and write queues.
At least the following macros shall be defined for use with I_SETSIG:
S_RDNORM
A normal (priority band set to 0) message has arrived at the
head of a STREAM head read queue.
S_RDBAND
A message with a non-zero priority band has arrived at the head
of a STREAM head read queue.
S_INPUT
A message, other than a high-priority message, has arrived at
the head of a STREAM head read queue.
S_HIPRI
A high-priority message is present on a STREAM head read queue.
S_OUTPUT
The write queue for normal data (priority band 0) just below the
STREAM head is no longer full. This notifies the process that
there is room on the queue for sending (or writing) normal data
downstream.
S_WRNORM
Equivalent to S_OUTPUT.
S_WRBAND
The write queue for a non-zero priority band just below the
STREAM head is no longer full.
S_MSG A STREAMS signal message that contains the SIGPOLL signal
reaches the front of the STREAM head read queue.
S_ERROR
Notification of an error condition reaches the STREAM head.
S_HANGUP
Notification of a hangup reaches the STREAM head.
S_BANDURG
When used in conjunction with S_RDBAND, SIGURG is generated
instead of SIGPOLL when a priority message reaches the front of
the STREAM head read queue.
At least the following macros shall be defined for use with I_PEEK:
RS_HIPRI
Only look for high-priority messages.
At least the following macros shall be defined for use with I_SRDOPT:
RNORM Byte-STREAM mode, the default.
RMSGD Message-discard mode.
RMSGN Message-non-discard mode.
RPROTNORM
Fail read() with [EBADMSG] if a message containing a control
part is at the front of the STREAM head read queue.
RPROTDAT
Deliver the control part of a message as data when a process
issues a read().
RPROTDIS
Discard the control part of a message, delivering any data part,
when a process issues a read().
At least the following macros shall be defined for use with I_SWOPT:
SNDZERO
Send a zero-length message downstream when a write() of 0 bytes
occurs.
At least the following macros shall be defined for use with I_ATMARK:
ANYMARK
Check if the message is marked.
LASTMARK
Check if the message is the last one marked on the queue.
At least the following macros shall be defined for use with I_UNLINK:
MUXID_ALL
Unlink all STREAMs linked to the STREAM associated with fildes.
The following macros shall be defined for getmsg(), getpmsg(),
putmsg(), and putpmsg():
MSG_ANY
Receive any message.
MSG_BAND
Receive message from specified band.
MSG_HIPRI
Send/receive high-priority message.
MORECTL
More control information is left in message.
MOREDATA
More data is left in message.
The <stropts.h> header may make visible all of the symbols from
<unistd.h>.
The following shall be declared as functions and may also be defined as
macros. Function prototypes shall be provided.
int isastream(int);
int getmsg(int, struct strbuf *restrict, struct strbuf *restrict,
int *restrict);
int getpmsg(int, struct strbuf *restrict, struct strbuf *restrict,
int *restrict, int *restrict);
int ioctl(int, int, ... );
int putmsg(int, const struct strbuf *, const struct strbuf *, int);
int putpmsg(int, const struct strbuf *, const struct strbuf *, int,
int);
int fattach(int, const char *);
int fdetach(const char *);
The following sections are informative.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
<sys/types.h> , <unistd.h> , the System Interfaces volume of
IEEE Std 1003.1-2001, close(), fcntl(), getmsg(), ioctl(), open(),
pipe(), read(), poll(), putmsg(), signal(), write()
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version 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 .