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Top Forums Shell Programming and Scripting On how to select the right tool for a given task Post 302248839 by bakunin on Monday 20th of October 2008 12:38:23 AM
Old 10-20-2008
I agree with perderabo that any use of an external program is costly in terms of system calls. So in fact we are not talking about sed (or awk) but about the usage of any program external to the shell.

I doubt that any of us can write a meaningful shellscript without any calls to external programs. I even doubt that it is possible to write such a script without any calls to external programs inside loops.

And as an example for an operation on a variable which is probably easier (and faster) to do in an external program than with shell means: perform a rot13 encryption on the contents of a string variable. In external programs this is one call (here with tr, with sed or awk its equally simple):

print - $var | tr 'abcdefghijklmnopqrstuvwxyz' 'nopqrstuvwxyzabcdefghijklm'

The same in shell variable expansion??

bakunin
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wxFileDialog(3erl)					     Erlang Module Definition						wxFileDialog(3erl)

NAME
wxFileDialog - See external documentation: wxFileDialog. DESCRIPTION
See external documentation: wxFileDialog . This class is derived (and can use functions) from: wxDialog wxTopLevelWindow wxWindow wxEvtHandler DATA TYPES
wxFileDialog() : An object reference, The representation is internal and can be changed without notice. It can't be used for comparsion stored on disc or distributed for use on other nodes. EXPORTS
new(Parent::wxWindow() (see module wxWindow)) -> wxFileDialog() Equivalent to new(Parent, []) . new(Parent::wxWindow() (see module wxWindow), Options::[Option]) -> wxFileDialog() Types Option = {message, string()} | {defaultDir, string()} | {defaultFile, string()} | {wildCard, string()} | {style, integer()} | {pos, {X::integer(), Y::integer()}} | {sz, {W::integer(), H::integer()}} See external documentation . getDirectory(This::wxFileDialog()) -> string() See external documentation . getFilename(This::wxFileDialog()) -> string() See external documentation . getFilenames(This::wxFileDialog()) -> [[string()]] See external documentation . getFilterIndex(This::wxFileDialog()) -> integer() See external documentation . getMessage(This::wxFileDialog()) -> string() See external documentation . getPath(This::wxFileDialog()) -> string() See external documentation . getPaths(This::wxFileDialog()) -> [[string()]] See external documentation . getWildcard(This::wxFileDialog()) -> string() See external documentation . setDirectory(This::wxFileDialog(), Dir::string()) -> ok See external documentation . setFilename(This::wxFileDialog(), Name::string()) -> ok See external documentation . setFilterIndex(This::wxFileDialog(), FilterIndex::integer()) -> ok See external documentation . setMessage(This::wxFileDialog(), Message::string()) -> ok See external documentation . setPath(This::wxFileDialog(), Path::string()) -> ok See external documentation . setWildcard(This::wxFileDialog(), WildCard::string()) -> ok See external documentation . destroy(This::wxFileDialog()) -> ok Destroys this object, do not use object again AUTHORS
<> wxErlang 0.98.9 wxFileDialog(3erl)
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