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Diffstat (limited to 'static/v10/man5/mpxio.5')
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diff --git a/static/v10/man5/mpxio.5 b/static/v10/man5/mpxio.5 deleted file mode 100644 index 11479a8e..00000000 --- a/static/v10/man5/mpxio.5 +++ /dev/null @@ -1,187 +0,0 @@ -.TH MPXIO 5 -.UC 4 -.SH NAME -mpxio \- multiplexed i/o -.SH SYNOPSIS -.B #include <sys/mx.h> -.PP -.B #include <sgtty.h> -.SH DESCRIPTION -Data transfers on -mpx files -(see -.IR mpx (2)) -are multiplexed by -imposing -a record structure on the io stream. -Each record represents data -from/to -a particular channel or -a control or status message associated with a particular channel. -.PP -The prototypical data record read from an mpx file is as follows -.PP -.in +.5i -.nf -struct input_record { - short index; - short count; - short ccount; - char data[]; -}; -.PP -.fi -where -.I index -identifies the channel, -and -.I count -specifies the number of characters in -.I data. -If -.I count -is zero, -.I ccount -gives the size of -.I data, -and the record is a control or status message. -Although -.I count -or -.I ccount -might be odd, -the operating system aligns records -on short (i.e. 16\-bit) boundaries -by skipping bytes when necessary. -.PP -Data written to an mpx file must be formatted as an array -of record structures defined as follows -.PP -.in +.5i -.nf -struct output_record { - short index; - short count; - short ccount; - char *data; -}; -.fi -.PP -where the data portion of the record is referred -to indirectly and the other cells have the same interpretation -as in -.I input_record. -.PP -The -control messages listed below may be read from -a multiplexed file descriptor. -They are presented as two 16-bit integers: -the first number is the message code -(defined in -.IR <sys/mx.h> ), -the second is an optional parameter meaningful -only with M_WATCH, M_BLK, and M_SIG. -.PP -.TP "\w'M_WATCH 'u" -M_WATCH -a process `wants to attach' on this channel. -The second parameter is the 16-bit -user-id of the process that executed the open. -.TP -M_CLOSE -the channel is closed. -This message is generated when the last -file descriptor referencing -a channel is closed. -The -.I detach -command -(see -.IR mpx (2) -should be used in response to this message. -.TP -M_EOT -indicates logical end of file on a channel. -If the channel is joined to a typewriter, -EOT (control-d) -will cause the M_EOT message -under the conditions specified in -.IR tty (4) -for end of file. -If the channel is attached to a process, -M_EOT will be generated whenever the process -writes zero bytes on the channel. -.TP -M_BLK -if non-blocking mode has been enabled on an -mpx file descriptor -.I xd -by executing -.IR "ioctl(xd, MXNBLK, 0)" , -write operations on the file are truncated in the kernel -when internal queues become full. -This is done on a per-channel basis: -the parameter -is a count of the number of characters -not transferred to the channel on which -M_BLK is received. -.TP -M_UBLK -is generated for a channel -after M_BLK when the internal queues have -drained below a threshold. -.TP -M_SIG -is generated instead of a normal asynchronous -signal on channels that are joined to typewriters. -The parameter is the signal number. -.PP -Two other messages may be generated by the kernel. -As with other messages, the first -16-bit quantity is the message code. -.br -.TP "\w'M_IOCTL 'u" -M_OPEN -is generated in conjunction with -`listener' mode (see -.IR mpx (2)). -The uid of the calling process follows the message code -as with M_WATCH. -This is followed by a null-terminated string -which is the name of the file being opened. -.TP -M_IOCTL -is generated for a channel connected -to a process -when that process executes the -.I "ioctl(fd, cmd, &vec)" -call on the channel file descriptor. -The M_IOCTL code is followed by -the -.I cmd -argument given to -.I ioctl -followed by -the contents of the structure -.I vec. -It is assumed, -not needing a better compromise at this time, -that the length of -.I vec -is determined by -.I "sizeof (struct sgttyb)" -as declared in -.IR <sgtty.h> . -.in -1i -.PP -Two control messages are understood by the operating system. -M_EOT may be sent through an mpx file to a channel. -It is equivalent to propagating a zero-length record -through the channel; -i.e. the channel is allowed to drain and the process or -device at the other end receives a zero-length -transfer before data starts flowing through the channel again. -M_IOANS can also be sent through a channel to reply to a M_IOCTL. -The format is identical to that received from M_IOCTL. -.SH SEE ALSO -mpx(2) |