On 10/19/15 1:36 PM, Ken Irving wrote:
> The manpage section on process substitution could perhaps present the
> concept more clearly by starting with something like the sentence just
> above, e.g., very roughly:
>
> Process Substitution, taking the form of <(list) or >(list),
> expands the process list to a filename, allowing the construct to
> be used in place of a filename for output or input to a command.
> It is supported on systems that support named pipes (FIFOs) or the
> /dev/fd method of naming open files. ...
>
> The section goes right into what seems like implementation details, and
> the use of it is only mentioned in the fourth sentence or so.
Good suggestion. How about something like this:
Process substitution allows a process's input or output to be referred
to using a filename. It takes the form of <(list) or >(list). The
process list is run asynchronously, and its input or output appears as
a filename. This filename is passed as an argument to the current com-
mand as the result of the expansion. If the >(list) form is used,
writing to the file will provide input for list. If the <(list) form
is used, the file passed as an argument should be read to obtain the
output of list. Process substitution is supported on systems that sup-
port named pipes (FIFOs) or the /dev/fd method of naming open files.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU [email protected] http://cnswww.cns.cwru.edu/~chet/
