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info(n)			     Tcl Built-In Commands		       info(n)

______________________________________________________________________________

NAME
       info - Return information about the state of the	Tcl interpreter

SYNOPSIS
       info option ?arg	arg ...?
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DESCRIPTION
       This  command  provides	information about various internals of the Tcl
       interpreter.  The legal options (which may be abbreviated) are:

       info args procname
	      Returns a	list containing	the names of the arguments  to	proce-
	      dure  procname,  in  order.   Procname must be the name of a Tcl
	      command procedure.

       info body procname
	      Returns the body of procedure procname.  Procname	 must  be  the
	      name of a	Tcl command procedure.

       info cmdcount
	      Returns  a  count	of the total number of commands	that have been
	      invoked in this interpreter.

       info commands ?pattern?
	      If pattern is not	specified, returns a list of names of all  the |
	      Tcl  commands visible (i.e. executable without using a qualified |
	      name) to the current namespace, including	both the built-in com- |
	      mands  written in	C and the command procedures defined using the |
	      proc command.  If	pattern	is specified, only those names	match- |
	      ing pattern are returned.	 Matching is determined	using the same |
	      rules as for string match.  pattern can be a qualified name like |
	      Foo::print*.  That is, it	may specify a particular namespace us- |
	      ing a sequence of	namespace names	 separated  by	double	colons |
	      (::),  and  may  have pattern matching special characters	at the |
	      end to specify a set of commands in that namespace.  If  pattern |
	      is  a  qualified	name,  the resulting list of command names has |
	      each one qualified with the name of the specified	namespace, and |
	      only the commands	defined	in the named namespace are returned.

       info complete command
	      Returns  1  if command is	a complete Tcl command in the sense of
	      having no	unclosed quotes, braces,  brackets  or	array  element
	      names.   If the command does not appear to be complete then 0 is
	      returned.	 This command is typically used	in line-oriented input
	      environments to allow users to type in commands that span	multi-
	      ple lines;  if the command is not	complete, the script can delay
	      evaluating it until additional lines have	been typed to complete
	      the command.

       info default procname arg varname
	      Procname must be the name	of a Tcl  command  procedure  and  arg
	      must  be the name	of an argument to that procedure.  If arg does
	      not have a default value then the	command	returns	0.   Otherwise
	      it  returns  1 and places	the default value of arg into variable
	      varname.

       info exists varName
	      Returns 1	if the variable	named varName exists  in  the  current
	      context  (either as a global or local variable) and has been de-
	      fined by being given a value, returns 0 otherwise.

       info frame ?number?
	      This command provides access to all frames on  the  stack,  even
	      those  hidden  from info level. If number	is not specified, this
	      command returns a	number giving the frame	level of the  command.
	      This  is	1 if the command is invoked at top-level. If number is
	      specified, then the result is a dictionary containing the	 loca-
	      tion  information	 for  the command at the numbered level	on the
	      stack.

	      If number	is positive (> 0) then it selects a  particular	 stack
	      level (1 refers to the top-most active command, i.e., info frame
	      itself, 2	to the command it was called from, and so on);	other-
	      wise  it gives a level relative to the current command (0	refers
	      to the current command, i.e.,  info  frame  itself,  -1  to  its
	      caller, and so on).

	      This  is	similar	to how info level works, except	that this sub-
	      command reports all frames, like	sourced	 scripts,  evals,  up-
	      levels, etc.

	      Note  that  for  nested commands,	like "foo [bar [x]]", only "x"
	      will be seen by an info frame invoked within "x".	 This  is  the
	      same as for info level and error stack traces.

	      The  result  dictionary  may contain the keys listed below, with
	      the specified meanings for their values:

	      type   This entry	is always present and describes	the nature  of
		     the  location  for	the command. The recognized values are
		     source, proc, eval, and precompiled.

		     source
			    means that the command is found in a script	loaded
			    by the source command.

		     proc
			    means  that	 the  command  is found	in dynamically
			    created procedure body.

		     eval
			    means that the command is executed by eval or  up-
			    level.

		     precompiled
			    means  that	 the command is	found in a precompiled
			    script (loadable by	the package tbcload),  and  no
			    further information	will be	available.

	      line   This entry	provides the number of the line	the command is
		     at	inside of the script it	is a part of. This information
		     is	not present for	type precompiled. For type source this
		     information is counted relative to	the beginning  of  the
		     file,  whereas for	the last two types the line is counted
		     relative to the start of the script.

	      file   This entry	is present only	for type source.  It  provides
		     the normalized path of the	file the command is in.

	      cmd    This entry	provides the string representation of the com-
		     mand. This	is usually the unsubstituted form, however for
		     commands which are	a pure list executed by	eval it	is the
		     substituted form as they have no other string representa-
		     tion.  Care  is  taken that the pure-List property	of the
		     latter is not spoiled.

	      proc   This entry	is present only	if the command is found	in the
		     body  of  a  regular  Tcl procedure. It then provides the
		     name of that procedure.

	      lambda This entry	is present only	if the command is found	in the
		     body  of  an  anonymous  Tcl procedure, i.e. a lambda. It
		     then provides the entire  definition  of  the  lambda  in
		     question.

	      level  This  entry  is  present  only if the queried frame has a
		     corresponding frame returned by info level.  It  provides
		     the index of this frame, relative to the current level (0
		     and negative numbers).

	      A	thing of note is that for  procedures  statically  defined  in
	      files the	locations of commands in their bodies will be reported
	      with type	source and absolute line  numbers,  and	 not  as  type
	      proc.  The  same is true for procedures nested in	statically de-
	      fined procedures,	and literal eval scripts in  files  or	stati-
	      cally defined procedures.

	      In contrast, a procedure definition or eval within a dynamically
	      evaluated	environment count linenumbers relative to the start of
	      their  script,  even  if they would be able to count relative to
	      the start	of the outer dynamic script. That type of number  usu-
	      ally makes more sense.

	      A	 different way of describing this behaviour is that file based
	      locations	are tracked as deeply as possible, and where  this  is
	      not  possible the	lines are counted based	on the smallest	possi-
	      ble eval or procedure body, as that scope	is usually  easier  to
	      find than	any dynamic outer scope.

	      The syntactic form {*} is	handled	like eval. I.e.	if it is given
	      a	literal	list argument the system tracks	the linenumber	within
	      the  list	 words	as  well,  and	otherwise  all linenumbers are
	      counted relative to the start of each word (smallest scope)

       info functions ?pattern?
	      If pattern is not	specified, returns a  list  of	all  the  math
	      functions	 currently  defined.   If  pattern  is specified, only
	      those functions whose name matches pattern are returned.	Match-
	      ing is determined	using the same rules as	for string match.

       info globals ?pattern?
	      If  pattern is not specified, returns a list of all the names of
	      currently-defined	global variables.  Global variables are	 vari-
	      ables  in	 the  global namespace.	 If pattern is specified, only
	      those names matching pattern are returned.  Matching  is	deter-
	      mined using the same rules as for	string match.

       info hostname
	      Returns the name of the computer on which	this invocation	is be-
	      ing executed.  Note that this name is not	guaranteed to  be  the
	      fully  qualified	domain	name of	the host.  Where machines have
	      several different	names (as  is  common  on  systems  with  both
	      TCP/IP  (DNS) and	NetBIOS-based networking installed,) it	is the
	      name that	is suitable for	TCP/IP networking that is returned.

       info level ?number?
	      If number	is not specified, this command returns a number	giving
	      the  stack  level	of the invoking	procedure, or 0	if the command
	      is invoked at top-level.	If number is specified,	then  the  re-
	      sult is a	list consisting	of the name and	arguments for the pro-
	      cedure call at level number on the stack.	 If number is positive
	      then  it	selects	a particular stack level (1 refers to the top-
	      most active procedure, 2 to the procedure	it called, and so on);
	      otherwise	 it  gives  a  level  relative to the current level (0
	      refers to	the current procedure, -1 to its caller, and  so  on).
	      See  the uplevel command for more	information on what stack lev-
	      els mean.

       info library
	      Returns the name of the library directory	in which standard  Tcl
	      scripts  are  stored.  This is actually the value	of the tcl_li-
	      brary variable and may be	changed	by setting  tcl_library.   See
	      the tclvars manual entry for more	information.

       info loaded ?interp?
	      Returns  a  list	describing  all	of the packages	that have been
	      loaded into interp with the load command.	 Each list element  is
	      a	 sub-list with two elements consisting of the name of the file
	      from which the package was loaded	and the	name of	 the  package.
	      For  statically-loaded  packages	the file name will be an empty
	      string.  If interp is omitted then information is	 returned  for
	      all packages loaded in any interpreter in	the process.  To get a
	      list of just the packages	in the current interpreter, specify an
	      empty string for the interp argument.

       info locals ?pattern?
	      If  pattern is not specified, returns a list of all the names of
	      currently-defined	local variables, including  arguments  to  the
	      current  procedure,  if any.  Variables defined with the global,
	      upvar  and variable commands will	not be returned.   If  pattern
	      is  specified,  only  those names	matching pattern are returned.
	      Matching is determined using the same rules as for string	match.

       info nameofexecutable
	      Returns the full path name of the	binary file from which the ap-
	      plication	 was invoked.  If Tcl was unable to identify the file,
	      then an empty string is returned.

       info patchlevel
	      Returns the value	of the global variable tcl_patchLevel; see the
	      tclvars manual entry for more information.

       info procs ?pattern?
	      If  pattern is not specified, returns a list of all the names of
	      Tcl command procedures in	the current namespace.	If pattern  is
	      specified,  only	those procedure	names in the current namespace
	      matching pattern are returned.  Matching is determined using the
	      same  rules  as for string match.	 If pattern contains any name-
	      space separators,	they are used to select	a  namespace  relative
	      to the current namespace (or relative to the global namespace if
	      pattern starts with ::) to match within; the matching pattern is
	      taken to be the part after the last namespace separator.

       info script ?filename?
	      If a Tcl script file is currently	being evaluated	(i.e. there is
	      a	call to	Tcl_EvalFile active or there is	an  active  invocation
	      of  the  source  command), then this command returns the name of
	      the innermost file being processed.  If filename	is  specified,
	      then  the	 return	value of this command will be modified for the
	      duration of the active invocation	to return that name.  This  is
	      useful  in virtual file system applications.  Otherwise the com-
	      mand returns an empty string.

       info sharedlibextension
	      Returns the extension used on this platform  for	the  names  of
	      files  containing	 shared	 libraries (for	example, .so under So-
	      laris).  If shared libraries are not supported on	this  platform
	      then an empty string is returned.

       info tclversion
	      Returns  the  value  of the global variable tcl_version; see the
	      tclvars manual entry for more information.

       info vars ?pattern?
	      If pattern is not	specified, returns a list of all the names  of
	      currently-visible	 variables.   This  includes  locals  and cur-
	      rently-visible globals.  If pattern  is  specified,  only	 those
	      names matching pattern are returned.  Matching is	determined us-
	      ing the same rules as for	string match.  pattern can be a	quali-
	      fied name	like Foo::option*.  That is, it	may specify a particu-
	      lar namespace using a sequence of	namespace names	 separated  by
	      double  colons (::), and may have	pattern	matching special char-
	      acters at	the end	to specify a set of variables  in  that	 name-
	      space.   If  pattern  is a qualified name, the resulting list of
	      variable names has each matching	namespace  variable  qualified
	      with  the	 name of its namespace.	 Note that a currently-visible
	      variable may not yet "exist" if it has  not  been	 set  (e.g.  a
	      variable declared	but not	set by variable).

EXAMPLE
       This  command  prints  out  a  procedure	 suitable  for saving in a Tcl
       script:

	      proc printProc {procName}	{
		  set result [list proc	$procName]
		  set formals {}
		  foreach var [info args $procName] {
		      if {[info	default	$procName $var def]} {
			  lappend formals [list	$var $def]
		      }	else {
			  # Still need the list-quoting	because	variable
			  # names may properly contain spaces.
			  lappend formals [list	$var]
		      }
		  }
		  puts [lappend	result $formals	[info body $procName]]
	      }

SEE ALSO
       global(n), proc(n)

KEYWORDS
       command,	information, interpreter, level, namespace,  procedure,	 vari-
       able

Tcl				      8.4			       info(n)

NAME | SYNOPSIS | DESCRIPTION | EXAMPLE | SEE ALSO | KEYWORDS

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