Supplementary routines

gtk-fortran High Level API

Supplementary material

This module contains some supplementary material useful for writing GTK programs in Fortran. The functions are not listed in the gtk-fortran-index.csv file, either because they are not (currenty) extracted by the automatic tools, or because they are just convenient functions added here.

module gtk_sup

Currently it contains:

• GTYPE: Definitions of the integer length and the values for each type.
• GtkTreeIter: Type definition, and its clear procedure.
• GValue: Pseudo type definition, and its clear procedure.
• GtkTextIter: Type definition.
• GError: Type definition.
• Interfaces for string conversions.
• Boolean conversion routines.
• Miscellaneous functions.

Gtype

The various Gtype definitions from the gtype.h file.

Iterators and Gvalues

These structures are always allocated in the calling program, rather than being declared as pointers and leaving GTK to allocate them.

• GtkTreeIter, Iterator for TreeView widgets
• GtkTextIter, Iterator for TextView widgets
• GValue, A value container.

GError

GError is a transparent structure that returns error information.

clear_gtktreeiter

  subroutine clear_gtktreeiter(iter)
    type(gtktreeiter), intent(inout) :: iter

Clear a tree iterator

Argument	Type	Required?	Description
ITER	gtktreeiter	required	The iterator to clear

clear_gvalue

  subroutine clear_gvalue(gval)
    type(gvalue), intent(inout) :: gval

Clear a GValue

Argument	Type	Required?	Description
GVAL	gvalue	required	The GValue to clear.

c_f_string_copy_alloc

  subroutine c_f_string_copy_alloc(the_ptr, f_string)
    type(c_ptr), intent(in) :: the_ptr
    character(:), intent(out), allocatable :: f_string
    character(kind=c_char), pointer :: f_array(:)
    integer :: i

Create a default character deferred length allocatable copy of the value of a C string. This function should be preferred to c_f_string_copy() when using a Fortran>=2008 compiler. An advantage is that the trim() function will generally not be needed.

Argument	Type	Required?	Description
THE_PTR	string	required	The C string to be converted.
F_STRING	f_string	required	A Scalar Fortran string.

c_f_string_copy

  subroutine c_f_string_copy(the_ptr, f_string, status)
    type(c_ptr), intent(in) :: the_ptr
    character(*), intent(out) :: f_string
    integer, intent(out), optional :: status
    character(kind=c_char), pointer :: f_array(:)
    integer :: i

Create a default character fixed length copy of the value of a C string.

Argument	Type	Required?	Description
THE_PTR	string	required	The C string to be converted.
F_STRING	f_string	required	A Scalar Fortran string.
STATUS	integer	optional	Is set to -1 if the Fortran string is too short.

If the Fortran string is too short, the C string is truncated.

c_f_string_chars

  subroutine c_f_string_chars(c_string, f_string)
    character(len=1, kind=C_char), intent(in) :: c_string(*)
    character(len=*), intent(out) :: f_string
    integer :: i

Copy a C string, passed as a char-array reference, to a Fortran string. String routine from C_interface_module by Joseph M. Krahn: http://fortranwiki.org/fortran/show/c_interface_module

Argument	Type	Required?	Description
C_STRING	chars array	required	The C chars array to be converted.
F_STRING	f_string	required	A Scalar Fortran string.

c_f_string_ptr

  subroutine c_f_string_ptr(c_string, f_string)
    type(C_ptr), intent(in) :: c_string
    character(len=*), intent(out) :: f_string
    character(len=1, kind=C_char), dimension(:), pointer :: p_chars
    integer :: i

Copy a C string, passed by pointer, to a Fortran string. If the C pointer is NULL, the Fortran string is blanked. c_string must be NUL terminated, or at least as long as f_string. If c_string is longer, it is truncated. Otherwise, f_string is blank-padded at the end.

Argument	Type	Required?	Description
C_STRING	string	required	The C string to be converted.
F_STRING	f_string	required	A Scalar Fortran string.

convert_c_string_scalar

  subroutine convert_c_string_scalar(textptr, f_string, status)
    character(kind=c_char), dimension(:), intent(in) :: textptr
    character(len=*), intent(out) :: f_string
    integer(c_int), intent(out), optional :: status

Convert a null-terminated C-string to a Fortran string

Argument	Type	Required?	Description
TEXTPTR	string	required	The C string to be converted.
F_STRING	f_string	required	A Scalar Fortran string.
STATUS	integer	optional	Is set to -1 if the Fortran string is too short.

Usually called via the convert_c_string generic interface.

convert_c_string_array

  subroutine convert_c_string_array(textptr, f_string, status)
    character(kind=c_char), dimension(:), intent(in) :: textptr
    character(len=*), intent(out), dimension(:), allocatable :: f_string
    integer, intent(out), optional :: status

Convert a null-terminated LF-separated C-string into a Fortran string array

Argument	Type	Required?	Description
TEXTPTR	string	required	The C string to be converted.
F_STRING	f_string()	required	A Fortran string array.
STATUS	integer	optional	Is set to -1 if the Fortran string is too short for any line.

Usually called via the convert_c_string generic interface.

convert_c_string_scalar_cptr

  subroutine convert_c_string_scalar_cptr(ctext, f_string, status)
    type(c_ptr), intent(in) :: ctext
    character(len=*), intent(out) :: f_string
    integer, intent(out), optional :: status

Convert a null-terminated C-string to a Fortran string

Argument	Type	Required?	Description
CTEXT	c_ptr	required	A C poiner to string to be converted.
F_STRING	f_string	required	A Scalar Fortran string.
STATUS	integer	optional	Is set to -1 if the Fortran string is too short.

Usually called via the convert_c_string generic interface.

convert_c_string_array_cptr

  subroutine convert_c_string_array_cptr(ctext, f_string, status)
    type(c_ptr), intent(in) :: ctext
    character(len=*), intent(out), dimension(:), allocatable :: f_string
    integer, intent(out), optional :: status

Convert a null-terminated LF-separated C-string into a Fortran string array

Argument	Type	Required?	Description
CTEXT	c_ptr	required	A C poiner to string to be converted.
F_STRING	f_string()	required	A Fortran string. array
STATUS	integer	optional	Is set to -1 if the Fortran string is too short for any of the lines.

Usually called via the convert_c_string generic interface.

convert_f_string_a

  subroutine convert_f_string_a(f_string, textptr, length)
    character(len=*), intent(in), dimension(:) :: f_string
    character(kind=c_char), dimension(:), intent(out), allocatable :: textptr
    integer(c_int), intent(out), optional :: length

Convert a Fortran string array into a null-terminated, LF_separated C-string

Argument	Type	Required?	Description
F_STRING	f_string	required	The Fortran string to convert
TEXTPR	string	required	A C type string, (allocatable).
LENGTH	c_int	optional	The length of the generated C string.

convert_f_string_s

  subroutine convert_f_string_s(f_string, textptr, length)
    character(len=*), intent(in) :: f_string
    character(kind=c_char), dimension(:), intent(out), allocatable :: textptr
    integer(c_int), intent(out), optional :: length

Convert a Fortran string into a null-terminated C-string

Argument	Type	Required?	Description
F_STRING	f_string	required	The Fortran string to convert
TEXTPR	string	required	A C type string, (allocatable).
LENGTH	c_int	optional	The length of the generated C string.

c_f_logical

  function c_f_logical(cbool)
    logical :: c_f_logical
    integer(c_int), intent(in) :: cbool

Convert a gboolean to a Fortran logical

Argument	Type	Required?	Description
CBOOL	boolean	required	The Gboolean to convert.

f_c_logical4

  function f_c_logical4(flog)
    integer(c_int) :: f_c_logical4
    logical, intent(in) :: flog

Convert a Fortran default logical to a gboolean

Argument	Type	Required?	Description
FLOG	logical	required	The Fortran logical to convert.

Usually accessed via the generic f_c_logical interface

f_c_logical1

  function f_c_logical1(flog)
    integer(c_int) :: f_c_logical1
    logical(1), intent(in) :: flog

Convert a Fortran 1-byte logical to a gboolean

Argument	Type	Required?	Description
FLOG	logical*1	required	The Fortran logical to convert.

Usually accessed via the generic f_c_logical interface

is_UNIX_OS

  function is_UNIX_OS()
    use g, only: g_get_current_dir

    logical :: is_UNIX_OS
    character(:), allocatable :: path

Returns .true. if the OS is of the UNIX type. On a Windows system, it will return .false. because an absolute path can not begin by a slash.

fdate

  function fdate()
    character(29) :: fdate
    character(8)  :: date
    character(10) :: time
    character(5)  :: zone

Returns date, time and timezone in a string without spaces, for example: 2022-05-06T15:58:43.790+02:00