02-17-2020
Quote:
Originally Posted by
arghvark
Well, that's interesting. I see from searching for "File Descriptor" that it refers to an integer that in turn refers to a 'file' (or a byte stream) for a process on a Unix system. I guess the only other thing I would like to know now is how to know whether the "&" is needed at a particular point on the command line. As we have it "2" indicated stderr, but "1" indicated a file named 1, and "&1" indicated stdout. How would I know when to include "&"?
Well, on the right side of
> and
< there can be a filename, so the
& prefix indicates it is a file descriptor.
On the left side it is clear that it's a file descriptor, so the bare number does it.
Note that
> is identical with
1> and
< is identical with
0<.
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find(n) [incr Tcl] find(n)
__________________________________________________________________________________________________________________________________________________
NAME
find - search for classes and objects
SYNOPSIS
itcl::find option ?arg arg ...?
_________________________________________________________________
DESCRIPTION
The find command is used to find classes and objects that are available in the current interpreter. Classes and objects are reported first
in the active namespace, then in all other namespaces in the interpreter.
The option argument determines what action is carried out by the command. The legal options (which may be abbreviated) are:
find classes ?pattern?
Returns a list of [incr Tcl] classes. Classes in the current namespace are listed first, followed by classes in all other names-
paces in the interpreter. If the optional pattern is specified, then the reported names are compared using the rules of the "string
match" command, and only matching names are reported.
If a class resides in the current namespace context, this command reports its simple name--without any qualifiers. However, if the
pattern contains :: qualifiers, or if the class resides in another context, this command reports its fully-qualified name. There-
fore, you can use the following command to obtain a list where all names are fully-qualified:
itcl::find classes ::*
find objects ?pattern? ?-class className? ?-isa className?
Returns a list of [incr Tcl] objects. Objects in the current namespace are listed first, followed by objects in all other names-
paces in the interpreter. If the optional pattern is specified, then the reported names are compared using the rules of the "string
match" command, and only matching names are reported. If the optional "-class" parameter is specified, this list is restricted to
objects whose most-specific class is className. If the optional "-isa" parameter is specified, this list is further restricted to
objects having the given className anywhere in their heritage.
If an object resides in the current namespace context, this command reports its simple name--without any qualifiers. However, if
the pattern contains :: qualifiers, or if the object resides in another context, this command reports its fully-qualified name.
Therefore, you can use the following command to obtain a list where all names are fully-qualified:
itcl::find objects ::*
KEYWORDS
class, object, search, import
itcl 3.0 find(n)