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Manual Reference Pages  - <stropts.h> (P)

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stropts.h - STREAMS interface (STREAMS)

CONTENTS

Synopsis
Description
Application Usage
Rationale
Future Directions
See Also
Copyright

#include <stropts.h>

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.

None.

None.

None.

<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()

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 .