info(n) Tcl Built-In Commands info(n)______________________________________________________________________________NAME
info - Return information about the state of the Tcl interpreter
SYNOPSIS
info option ?arg arg ...?
_________________________________________________________________DESCRIPTION
This command provides information about various internals of the Tcl
interpreter. The legal option's (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 isn't specified, returns a list of names of all the
Tcl commands in the current namespace, including both the built-
in commands written in C and the command procedures defined
using the proc command. If pattern is specified, only those
names matching 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 par‐
ticular namespace using 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.
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 doesn't 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 isn't 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
doesn't have a default value then the command returns 0. Other‐
wise it returns 1 and places the default value of arg into vari‐
able 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
defined by being given a value, returns 0 otherwise. │
info functions ?pattern? │
If pattern isn't specified, returns a list of all the math func‐ │
tions currently defined. If pattern is specified, only those │
functions whose name matches pattern are returned. Matching is │
determined using the same rules as for string match.
info globals ?pattern?
If pattern isn't 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
being 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
result is a list consisting of the name and arguments for the
procedure call at level number on the stack. If number is posi‐
tive 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_library 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 isn't 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
application 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 isn't 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 names‐
pace 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
Solaris). If shared libraries aren't 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 isn't 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
using the same rules as for string match. pattern can be a
qualified name like Foo::option*. That is, it may specify a
particular namespace using a sequence of namespace names sepa‐
rated by double colons (::), and may have pattern matching spe‐
cial characters at the end to specify a set of variables in that
namespace. 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 ALSOglobal(n), proc(n)KEYWORDS
command, information, interpreter, level, namespace, procedure, vari‐
able
Tcl 8.4 info(n)
