filesystems/spufs/spufs.rst

44        tem  calls like read(2) or write(2), but often support only a subset of
49        All files that support the read(2) operation also support readv(2)  and
57        possible operations, e.g. read access on the wbox file.
68        read(2), pread(2), write(2), pwrite(2), lseek(2)
81        The first SPU to CPU communication mailbox. This file is read-only  and
82        can  be  read  in  units of 32 bits.  The file can only be used in non-
86        read(2)
87               If  a  count smaller than four is requested, read returns -1 and
90               When data has been read successfully, four bytes are  placed  in
96        the first mailbox file, but can be read in blocking I/O mode,  and  the
100        read(2)
101               If a count smaller than four is requested, read returns  -1  and
109               When data has been read successfully, four bytes are  placed  in
129        reads  from  its PPE mailbox channel.  When data has been read success-
139        Read-only files that contain the length of the current queue, i.e.  how
140        many  words  can  be  read  from  mbox or ibox or how many words can be
141        written to wbox without blocking.  The files can be read only in 4-byte
145        read(2)
146               If a count smaller than four is requested, read returns  -1  and
149               read  from  (for  mbox_stat  and  ibox_stat)  or written to (for
157        can  be  used in read/write mode for debugging, but normal operation of
176        read(2)
177               When the count supplied to the read call  is  shorter  than  the
181               a running SPU task.  When a complete string has been  read,  all
182               subsequent read operations will return zero bytes and a new file
183               descriptor needs to be opened to read the value again.
197        read(2)
198               If  a  count smaller than four is requested, read returns -1 and
210        The two signal notification channels of an SPU.  These  are  read-write
213        files can be read from the SPU through a channel read or from host user
214        space through the file.  After the value has been read by the  SPU,  it
218        read(2)
219               If a count smaller than four is requested, read returns  -1  and
237        cation  files.  The  contain  a numerical ASCII string which is read as
244        read(2)
245               When the count supplied to the read call  is  shorter  than  the
248               pleting  the  string.  When a complete string has been read, all
249               subsequent read operations will return zero bytes and a new file
250               descriptor needs to be opened to read the value again.