ref: 6bb619c8db2867ddd9cd19c0aec05065f5ee0cae
dir: /man/1/alphabet-abc/
.TH ALPHABET-ABC 1
.SH NAME
abc \- alphabet declarations
.SH SYNOPSIS
.EX
load alphabet
typeset /abc
type /abc
.EE
.SH DESCRIPTION
.B Grid
is a typeset for
.I alphabet
(see
.IR sh-alphabet (1))
which enables
allows direct interconnection of
remote and local processing components. It defines one new type,
.BR endpoint ,
which represents
a place in the network to which two parties can
connect and exchange data.
.PP
In the following descriptions, if a type
is not
.B endpoint
or a type defined in the root typeset (see
.IR alphabet-main (1)),
it is assumed to be of type
.BR /string .
.PP
Modules currently provided within
the
.B /grid
typeset include:
.TP 10
\f5farm [\f5-lnkavA\fP] \fIendpoint\fP \fIaddr\fP \fItasktype\fP [\fIarg\fP...] -> \fIendpoint\fP
.B Farm
connects to a grid labour exchange (see
.IR scheduler (4))
at
.IR addr ,
starts a new job of type
.BR workflow ,
and passes all the data read from
.I endpoint
to be processed by the currently available labour.
The data is split into records, each one of which will be
processed on a worker node by
.IR tasktype ,
with its associated
.IR arg uments.
Other than
.BR -A ,
which specifies unauthenticated access to the
scheduler,
the various options are all passed verbatim to
.IR workflow :
.B -l
causes it to split its input on newline-separated records;
.B -n
specifies that no record separation is necessary on output;
.B -k
specifies that intermediate data for failed tasks should
be kept around;
.B -a
specifies that intermediate data for all tasks should
be kept around, and
.B -v
specifies that
.I workflow
should produce a wordy description of what it is doing.
.TP
\f5local\fP \fIendpoint\fP -> \fI/fd\fP
.B Local
reads everything from
.IR endpoint ,
and writes it to
.IR fd .
.TP
\f5remote\fP [-a \fIaddr\fP] \fIfd\fP -> \fIendpoint\fP
.B Remote
is the inverse of
.BR local :
it reads data from
.I fd
and writes it to a newly created endpoint.
If
.B -a
is given,
.I addr
specifies the network address of an endpoint server
on which to create the new endpoint.
.TP
\f5rexec\fP [\f5-A\fP] \fIendpoint\fP \fIaddr\fP \fIcmd\fP -> \fIendpoint\fP
.B Rexec
connects to a remote execution server at
.I addr
(unauthenticated if
.B -A
is specified), and arranges to execute the
.I alphabet
expression
.I cmd
there. The expression should be compatible with usage
.BR "fd -> fd" .
Data from the argument
.I endpoint
will be piped through this expression, and
made available as the resulting
.I endpoint
endpoint.
.SH EXAMPLES
The examples below that a local endpoint is available, and the following
.I alphabet
declarations:
.EX
load alphabet
typeset /grid
type /string /endpoint /fd
import /grid/local /grid/remote
autoconvert fd endpoint remote
.EE
Set up a rendering pipeline:
.EX
-{/read /tmp/somedata |
remote |
rexec tcp!node1!rexec "{(/fd); /filter $1 "{os render_stage1}} |
rexec tcp!node2!rexec "{(/fd); /filter $1 "{os render_stage2}} |
/create /tmp/somedata.result
}
.EE
.SH SOURCE
.BR /appl/alphabet/grid.b ,
.BR /appl/alphabet/gridtypes.b
.br
.B /appl/cmd/grid/*.b
.SH SEE ALSO
.IR sh-alphabet (1),
.IR alphabet-main (1),
.IR sh (1)