Tcl_PkgRequire(3) Tcl Library Procedures Tcl_PkgRequire(3)

____________________________________________________________________________

NAME

Tcl_PkgRequire, Tcl_PkgRequireEx, Tcl_PkgRequireProc, Tcl_PkgPresent,
Tcl_PkgPresentEx, Tcl_PkgProvide, Tcl_PkgProvideEx - package version
control

SYNOPSIS

#include <tcl.h>

const char *
Tcl_PkgRequire(interp, name, version, exact)

const char *
Tcl_PkgRequireEx(interp, name, version, exact, clientDataPtr)

int
Tcl_PkgRequireProc(interp, name, objc, objv, clientDataPtr)

const char *
Tcl_PkgPresent(interp, name, version, exact)

const char *
Tcl_PkgPresentEx(interp, name, version, exact, clientDataPtr)

int
Tcl_PkgProvide(interp, name, version)

int
Tcl_PkgProvideEx(interp, name, version, clientData)

ARGUMENTS

Tcl_Interp *interp (in) Interpreter where package is needed
or available.

const char *name (in) Name of package.

const char *version (in) A version specification string as
described for package require.

int exact (in) Non-zero means that only the
particular version specified by
version is acceptable. Zero means
that newer versions than version
are also acceptable as long as they
have the same major version number
as version.

const void *clientData (in) Arbitrary value to be associated
with the package.

void *clientDataPtr (out) Pointer to place to store the value
associated with the matching
package. It is only changed if the
pointer is not NULL and the
function completed successfully.
The storage can be any pointer type
with the same size as a void
pointer.

int objc (in) Number of requirements.

Tcl_Obj* objv[] (in) Array of requirements.
____________________________________________________________________________

DESCRIPTION

These procedures provide C-level interfaces to Tcl's package and
version management facilities.

Tcl_PkgRequire is equivalent to the package require command,
Tcl_PkgPresent is equivalent to the package present command, and
Tcl_PkgProvide is equivalent to the package provide command.

See the documentation for the Tcl commands for details on what these
procedures do.

If Tcl_PkgPresent or Tcl_PkgRequire complete successfully they return
a pointer to the version string for the version of the package that
is provided in the interpreter (which may be different than version);
if an error occurs they return NULL and leave an error message in the
interpreter's result.

Tcl_PkgProvide returns TCL_OK if it completes successfully; if an
error occurs it returns TCL_ERROR and leaves an error message in the
interpreter's result.

Tcl_PkgProvideEx, Tcl_PkgPresentEx and Tcl_PkgRequireEx allow the
setting and retrieving of the client data associated with the
package. In all other respects they are equivalent to the matching
functions.

Tcl_PkgRequireProc is the form of package require handling multiple
requirements. The other forms are present for backward compatibility
and translate their invocations to this form.

KEYWORDS

package, present, provide, require, version

SEE ALSO

package(n), Tcl_StaticPackage(3)

Tcl 7.5 Tcl_PkgRequire(3)