(recode.info)Sequencing

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Enter node , (file) or (file)node

Selecting sequencing methods
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   This program uses a few techniques when it is discovered that many
passes are needed to comply with the REQUEST.  For example, suppose
that four elementary steps were selected at recoding path optimisation
time.  Then `recode' will split itself into four different
interconnected tasks, logically equivalent to:

     STEP1 <INPUT | STEP2 | STEP3 | STEP4 >OUTPUT

   The splitting into subtasks is often done using Unix pipes.  But the
splitting may also be completely avoided, and rather simulated by using
memory buffer, or intermediate files.  The various
`--sequence=STRATEGY' options gives you control over the flow methods,
by replacing STRATEGY with `memory', `pipe' or `files'.  So, these
options may be used to override the default behaviour, which is also
explained below.

`--sequence=memory'
     When the recoding requires a combination of two or more elementary
     recoding steps, this option forces many passes over the data, using
     in-memory buffers to hold all intermediary results.

`-i'
`--sequence=files'
     When the recoding requires a combination of two or more elementary
     recoding steps, this option forces many passes over the data, using
     intermediate files between passes.  This is the default behaviour
     when files are recoded over themselves.  If this option is
     selected in filter mode, that is, when the program reads standard
     input and writes standard output, it might take longer for
     programs further down the pipe chain to start receiving some
     recoded data.

`-p'
`--sequence=pipe'
     When the recoding requires a combination of two or more elementary
     recoding steps, this option forces the program to fork itself into
     a few copies interconnected with pipes, using the `pipe(2)' system
     call.  All copies of the program operate in parallel.  This is the
     default behaviour in filter mode.  If this option is used when
     files are recoded over themselves, this should also save disk
     space because some temporary files might not be needed, at the
     cost of more system overhead.

     If, at installation time, the `pipe(2)' call is said to be
     unavailable, selecting option `-p' is equivalent to selecting
     option `-i'.  (This happens, for example, on MS-DOS systems.)