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Full Discussion: Echo eval xargs and other siblings
The Lounge What is on Your Mind? Echo eval xargs and other siblings Post 303031498 by Corona688 on Friday 1st of March 2019 10:32:16 AM
Old 03-01-2019
Shell evaluation is done automatically, by the shell, before a command is run. None of these except eval do shell evaluation; eval can do so because it's actually part of the shell!

By the same ticket, ls abc* is not a feature of ls. abc* gets evaluated by the shell before ls is executed.

I'm not sure what your >stdin stdin> are about. eval does not use stdin or stdout especially, unless the command it's evaluating does. It has no limits at all. That's what makes it dangerous.

One unique feature of xargs is that it parses single and double quotes. Usually this is considered an annoyance and worked around, but this can be used to your advantage, i.e. to split strings containing quotes without resorting to eval.
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LEARN ABOUT OPENSOLARIS

lower

lower(1T)						       Tk Built-In Commands							 lower(1T)

__________________________________________________________________________________________________________________________________________________

NAME

       lower - Change a window's position in the stacking order

SYNOPSIS

       lower window ?belowThis?
_________________________________________________________________

DESCRIPTION

       If  the belowThis argument is omitted then the command lowers window so that it is below all of its siblings in the stacking order (it will
       be obscured by any siblings that overlap it and will not obscure any siblings).	If belowThis is specified then it must be the path name of
       a  window  that	is either a sibling of window or the descendant of a sibling of window.  In this case the lower command will insert window
       into the stacking order just below belowThis (or the ancestor of belowThis that is a sibling of window); this could end up  either  raising
       or lowering window.

SEE ALSO

       raise

KEYWORDS

       lower, obscure, stacking order

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +--------------------+-----------------+
       |  ATTRIBUTE TYPE    | ATTRIBUTE VALUE |
       +--------------------+-----------------+
       |Availability	    | SUNWTk	      |
       +--------------------+-----------------+
       |Interface Stability | Uncommitted     |
       +--------------------+-----------------+
NOTES

       Source for Tk is available on http://opensolaris.org.

Tk									3.3								 lower(1T)
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