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From: relaxmike on 17 Jun 2008 10:39
And what if fortran strings were dynamic ?
Notice that fortran 2003 introduced the "character, allocatable"
statement.
Another possibility would be to make use of the m_vstring module
of the flibs project.
Suppose that the algorithm is separated into two parts :
1. the strings are added to a dynamic buffer,
2. the string string is written, depending on the modus :
- if dll mode, send the string,
- if stand alone mode, write the string to file.
This is a sketch (i did not test it) for the buffering algorithm.

The client code would be the following.

use bufferstring
use m_fileunit, only : fileunit_getfreeunit
call buffer_startup ()
call buffer_append ( "My 1st line." )
call buffer_append ( "My 2nd line." )
select case (modus)
case ( dll )
call sendstring ( buffer )
case ( standalone )
lunit = fileunit_getfreeunit ()
open ( lunit , file="myfile.log" )
call buffer_write ( lunit )
close ( lunit )
call buffer_shutdown ()

The buffering module would be like the following, with
a static dynamic buffer string and static methods to
fill the buffer.

module bufferstring
use m_vstring
type(t_vstring), save :: buffer
contains

subroutine buffer_startup()
call vstring_new ( buffer )
end subroutine buffer_startup

subroutine buffer_shutdown ()
call vstring_free ( buffer )
end subroutine buffer_shutdown

subroutine buffer_append ( string )
character(len=*) :: string
call vstring_append ( buffer , string )
end subroutine buffer_append

subroutine buffer_write ( lunit )
integer, intent (in) :: lunit
call buffer_writeinternal ( lunit , buffer )
contains
subroutine buffer_writeinternal ( lunit , buffer )
integer, intent (in) :: lunit
type(t_vstring), intent(in) :: buffer
character(len=vstring_length(buffer)) :: charstring
call vstring_cast ( buffer , charstring )
write ( lunit , "(A)") charstring
end subroutine buffer_writeinternal
end subroutine buffer_write
end module bufferstring

We could even use "call buffer_append ( VSTRING_NEWLINE )"
so that newlines characters are inserted between 2 appends.

Michaël

From: Terence on 18 Jun 2008 20:11
The write statements will refer to a file number.
This file number can be opened in one mode as a real named file on a
hard disk.
In the non-write mode, the file assigned should be the /NULL file.
So you choose which OPEN statement will be used, in a CASE construct.
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