flibs/m_vstrplatform(n) 1.0 "flibs"

NAME

flibs/m_vstrplatform - Platform-dependent routines and features

    TABLE OF CONTENTS
    SYNOPSIS
    DESCRIPTION
    OVERVIEW
        Dynamic or static buffer
        Pre-processing
    ROUTINES
    COPYRIGHT

SYNOPSIS

vstrplatform_system (command ?, status?)

vstrplatform_osstring() result ( currentos )

vstrplatform_platformstring() result ( currentplatform )

vstrplatform_getenvvar(envvar) result ( value )

vstrplatform_getenvvar(envvar) result ( value )

vstrplatform_cd ( dirname ?, status?)

vstrplatform_cd ( dirname ?, status?)

platform_stat ( filename , statarray ?, status?)

platform_stat ( filename , statarray ?, status?)

DESCRIPTION

The m_vstrplatform module provides several routines, which take dynamic strings arguments, to interact with the operating system.

The goal of this module is to provide system access with commands which take dynamic strings as arguments. It is based on m_platform, which takes character-based arguments. In the following example, extracted from the m_vfile module included in flibs, one sets the current working directory by using vstrplatform_cd on a dynamic string variable.

type ( t_vstring ) :: dirname integer :: status call vstrplatform_cd ( dirname , status )

This is a sketch of available routines :

vstrplatform_system Executes an external command on the system
vstrplatform_get_environment_variable Get to one environment variable
vstrplatform_cd Change the system current directory
vstrplatform_stat Get status of a file

Dynamic or static buffer

The internal algorithms provided by m_vstrplatform are based on basic fortran character strings. In several situations, the dynamic vstring has to be converted into a basic fortran character buffer string, which size has to be given explicitely in the source code, with the len = <something> statement (in the character ( len = <something>)).

If the _VSTRPLATFORM_STATIC_BUFFER macro is defined, then character strings of constant size VSTRPLATFORM_MAXIMUM_ENVVAR_LENGTH are used as buffers.
If the _VSTRPLATFORM_STATIC_BUFFER macro is not defined (which is the default), then character strings of dynamic size are used as buffers with the fortran 90 "len = vstring_length(this)" statement.

The second solution is more efficient, because the strings are not oversized or undersized, depending on the real number of characters in the dynamic string. But the feature may not be provided by the compiler at hand. For example, problems with the dynamic length character string have been experienced with Intel Fortran 8.

Pre-processing

The following preprocessing macro may be defined :

_VSTRPLATFORM_STATIC_BUFFER : see the section "Dynamic or static buffer"

ROUTINES

The module contains the following routines.

vstrplatform_system (command ?, status?)

type ( t_vstring ) :: command
integer, intent (out), optional :: status

Run an external command, optionally retrieving the status of that command. Under Windows the "call system" may generate the display of a console. If status is supplied, it contains 0 on success or nonzero error code upon return.

vstrplatform_osstring() result ( currentos )

type ( t_vstring ) :: currentos

Returns a string containing the current operating system running on the current machine, one of "Windows 95", "Windows NT", "MacOS", "SunOS", "Linux" or "Unix".

vstrplatform_platformstring() result ( currentplatform )

type ( t_vstring ) :: currentplatform

Returns a string containing the current platform running on the current machine, one of "Windows", "Mac", "Unix".

vstrplatform_getenvvar(envvar) result ( value )

type ( t_vstring ), intent(in) :: envvar
type ( t_vstring ) :: value

Returns the value of the environment variable envvar.

vstrplatform_getenvvar(envvar) result ( value )

character(len=*), intent(in) :: envvar
type ( t_vstring ) :: value

Same as previous with character(len=*) dirname.

vstrplatform_cd ( dirname ?, status?)

type(t_vstring), intent(in) :: dirname
integer, intent(out) , optional :: status

Change working directory to dirname. If status is supplied, it contains 0 on success or nonzero error code upon return

vstrplatform_cd ( dirname ?, status?)

character(len=*), intent(in) :: dirname
integer, intent(out) , optional :: status

Same as previous with character(len=*) dirname.

platform_stat ( filename , statarray ?, status?)

type(t_vstring), intent(in) :: filename
integer, dimension (1:13) , intent(out) :: filename
integer, intent(out) , optional :: status

Get status of the file filename and fills the array statarray with the following content.

statarray(1) Device ID
statarray(2) Inode number
statarray(3) File mode
statarray(4) Number of links
statarray(5) Owner's uid
statarray(6) Owner's gid
statarray(7) ID of device containing directory entry for file (0 if not available)
statarray(8) File size (bytes)
statarray(9) Last access time
statarray(10) Last modification time
statarray(11) Last file status change time
statarray(12) Preferred I/O block size (-1 if not available)
statarray(13) Number of blocks allocated (-1 if not available)

If status is supplied, it contains 0 on success or nonzero error code upon return

platform_stat ( filename , statarray ?, status?)

character(len=*), intent(in) :: filename
integer, dimension (1:13) , intent(out) :: filename
integer, intent(out) , optional :: status

Same as previous with character(len=*) dirname.