pm_sysShell::shell_type Type Reference

This is the shell_type class for generating objects to determine the runtime shell type of the operating system. More...

Public Attributes
type(shellis_type)	is
	The scalar object of type shellis_type whose logical components indicate the shell name. More...
character(1, SK)	dirsep = SK_"/"
	The scalar character of default kind SK of length 1 containing the preferred single-character shell directory separator (e.g., \ (Windows) or / (POSIX or if the shell type is unknown)). More...
character(1, SK)	pathsep = SK_":"
	The scalar character of default kind SK of length 1 containing the preferred single-character shell path separator (e.g., ; (Windows) or : (POSIX or if the shell type is unknown)). More...
character(:, SK), allocatable	dirseps
	The allocatable scalar character of default kind SK of arbitrary length containing all supported single-character shell directory separators (e.g., \/ (Windows) or / (POSIX or if the shell type is unknown)). More...
character(:, SK), allocatable	name
	The allocatable scalar character containing the name of or path to the current shell. More...

Detailed Description

This is the shell_type class for generating objects to determine the runtime shell type of the operating system.

Note that the system shells are frequently cross-platform.
For example,

1. Bash shell is frequently also available on Windows platforms.
2. Microsoft PowerShell Core (pwsh) is compliant with IEEE POSIX 1003.2 standard for Unix shells and can be installed on all major operating systems.

See the documentation of shellis_type for details and meaning of the is component of objects of this type.
Note that both gfortran as of version 12 and Intel ifort as of version 2022 use the Windows Command prompt as the default shell, even if the program is compiled and run from within a POSIX-compliant shell (like Git Bash).

Frequently, the runtime shell sh is merely a symlink to a more modern shell compatible with Bourne shell.
To ensure the target shell name is correctly inferred, the program will report the target of sh if it is a symlink.

Parameters

[out]	failed	: The output scalar logical of default kind LK that is .true. if and only if an error occurs while inferring the system shell name. (optional. If missing and a runtime error occurs, the program will halt by calling error stop.)
[in,out]	errmsg	: The input/output scalar character of default kind SK of arbitrary length type parameter. If an error occurs, errmsg will be set to a descriptive message about the nature of the runtime error. A length of LEN_IOMSG characters is likely sufficient to capture most error messages in full. (optional. It can be present only if failed is also present. If missing, no error message will be output.)

Returns

shell : The output scalar object of type shell_type containing the specifics of the runtime system shell.

Possible calling interfaces ⛓

use pm_kind, only: LK
use pm_sysShell, only: shell_type
character(255, SK) :: errmsg
type(shell_type) :: shell
logical(LK) :: failed
 
shell = shell_type()
shell = shell_type(failed)
shell = shell_type(failed, errmsg)

Remarks

The procedures under discussion are impure.

Note

Inferring the shell type at runtime is computationally expensive. Therefore, to avoid this extra computational cost, the procedures under this generic interface construct a static object of type shell_type which is saved within the procedures for internal usage in subsequent calls to the procedures.
The presence of such a sticky internal object should be fine even in threaded (e.g., OpenMP) applications, since the state of the object is initialized once and not changed anymore throughout the entire program life.

See also

shellis_type
isShellPosix
isShellWindows
Comparison of command shells

Example usage ⛓

program example
 
    use pm_kind, only: LK, IK, SK
    use pm_io, only: display_type
    use pm_sysShell, only: shell_type
 
    implicit none
 
    type(shell_type)    :: Shell
    logical(LK)         :: failed
    character(255, SK)  :: errmsg
 
    type(display_type)  :: disp
    disp = display_type(file = "main.out.F90")
 
    call disp%skip()
    call disp%show("shell = shell_type()")
                    shell = shell_type()
    call dispShell()
    call disp%skip()
 
    call disp%skip()
    call disp%show("shell = shell_type(failed)")
                    shell = shell_type(failed)
    call disp%show("failed ! Check if any error has occurred.")
    call disp%show( failed )
    if (failed) then
    call disp%show("SK_'error occurred.'")
    call disp%show( SK_'error occurred.' , deliml = SK_"""" )
    else
    call dispShell()
    end if
    call disp%skip()
 
    call disp%skip()
    call disp%show("shell = shell_type(failed, errmsg)")
                    shell = shell_type(failed, errmsg)
    call disp%show("failed ! Check if any error has occurred.")
    call disp%show( failed )
    if (failed) then
    call disp%show("errmsg")
    call disp%show( errmsg , deliml = SK_"""" )
    else
    call dispShell()
    end if
    call disp%skip()
 
contains
 
    subroutine dispShell()
        call disp%show("shell%is%ash        ")
        call disp%show( shell%is%ash         )
        call disp%show("shell%is%bash       ")
        call disp%show( shell%is%bash        )
        call disp%show("shell%is%csh        ")
        call disp%show( shell%is%csh         )
        call disp%show("shell%is%cmd        ")
        call disp%show( shell%is%cmd         )
        call disp%show("shell%is%dash       ")
        call disp%show( shell%is%dash        )
        call disp%show("shell%is%fish       ")
        call disp%show( shell%is%fish        )
        call disp%show("shell%is%ksh        ")
        call disp%show( shell%is%ksh         )
        call disp%show("shell%is%posix      ")
        call disp%show( shell%is%posix       )
        call disp%show("shell%is%powershell ")
        call disp%show( shell%is%powershell  )
        call disp%show("shell%is%sh         ")
        call disp%show( shell%is%sh          )
        call disp%show("shell%is%tcsh       ")
        call disp%show( shell%is%tcsh        )
        call disp%show("shell%is%windows    ")
        call disp%show( shell%is%windows     )
        call disp%show("shell%is%zsh        ")
        call disp%show( shell%is%zsh         )
        call disp%show("shell%is%yash       ")
        call disp%show( shell%is%yash        )
        call disp%show("shell%dirsep        ")
        call disp%show( shell%dirsep         , deliml = SK_"""" )
        call disp%show("shell%name          ")
        call disp%show( shell%name           , deliml = SK_"""" )
    end subroutine
 
end program example

Example Unix compile command via Intel ifort compiler ⛓

#!/usr/bin/env sh
rm main.exe
ifort -fpp -standard-semantics -O3 -Wl,-rpath,../../../lib -I../../../inc main.F90 ../../../lib/libparamonte* -o main.exe
./main.exe

Example Windows Batch compile command via Intel ifort compiler ⛓

del main.exe
set PATH=..\..\..\lib;%PATH%
ifort /fpp /standard-semantics /O3 /I:..\..\..\include main.F90 ..\..\..\lib\libparamonte*.lib /exe:main.exe
main.exe

Example Unix / MinGW compile command via GNU gfortran compiler ⛓

#!/usr/bin/env sh
rm main.exe
gfortran -cpp -ffree-line-length-none -O3 -Wl,-rpath,../../../lib -I../../../inc main.F90 ../../../lib/libparamonte* -o main.exe
./main.exe

Example output ⛓

 
shell = shell_type()
shell%is%ash        
F
shell%is%bash       
F
shell%is%csh        
F
shell%is%cmd        
F
shell%is%dash       
T
shell%is%fish       
F
shell%is%ksh        
F
shell%is%posix      
T
shell%is%powershell 
F
shell%is%sh         
F
shell%is%tcsh       
F
shell%is%windows    
F
shell%is%zsh        
F
shell%is%yash       
F
shell%dirsep        
"/"
shell%name          
"dash"
 
 
shell = shell_type(failed)
failed ! Check if any error has occurred.
F
shell%is%ash        
F
shell%is%bash       
F
shell%is%csh        
F
shell%is%cmd        
F
shell%is%dash       
T
shell%is%fish       
F
shell%is%ksh        
F
shell%is%posix      
T
shell%is%powershell 
F
shell%is%sh         
F
shell%is%tcsh       
F
shell%is%windows    
F
shell%is%zsh        
F
shell%is%yash       
F
shell%dirsep        
"/"
shell%name          
"dash"
 
 
shell = shell_type(failed, errmsg)
failed ! Check if any error has occurred.
F
shell%is%ash        
F
shell%is%bash       
F
shell%is%csh        
F
shell%is%cmd        
F
shell%is%dash       
T
shell%is%fish       
F
shell%is%ksh        
F
shell%is%posix      
T
shell%is%powershell 
F
shell%is%sh         
F
shell%is%tcsh       
F
shell%is%windows    
F
shell%is%zsh        
F
shell%is%yash       
F
shell%dirsep        
"/"
shell%name          
"dash"
 
 

Final Remarks ⛓

---

If you believe this algorithm or its documentation can be improved, we appreciate your contribution and help to edit this page's documentation and source file on GitHub.
For details on the naming abbreviations, see this page.
For details on the naming conventions, see this page.
This software is distributed under the MIT license with additional terms outlined below.

1. If you use any parts or concepts from this library to any extent, please acknowledge the usage by citing the relevant publications of the ParaMonte library.
   
2. If you regenerate any parts/ideas from this library in a programming environment other than those currently supported by this ParaMonte library (i.e., other than C, C++, Fortran, MATLAB, Python, R), please also ask the end users to cite this original ParaMonte library.
   

This software is available to the public under a highly permissive license.
Help us justify its continued development and maintenance by acknowledging its benefit to society, distributing it, and contributing to it.

Copyright

Computational Data Science Lab

Author:

Amir Shahmoradi, Tuesday March 7, 2017, 3:50 AM, Institute for Computational Engineering and Sciences (ICES), The University of Texas Austin

Definition at line 321 of file pm_sysShell.F90.

Member Data Documentation

dirsep

character(1, SK) pm_sysShell::shell_type::dirsep = SK_"/"

The scalar character of default kind SK of length 1 containing the preferred single-character shell directory separator (e.g., \ (Windows) or / (POSIX or if the shell type is unknown)).

Definition at line 323 of file pm_sysShell.F90.

dirseps

character(:, SK), allocatable pm_sysShell::shell_type::dirseps

The allocatable scalar character of default kind SK of arbitrary length containing all supported single-character shell directory separators (e.g., \/ (Windows) or / (POSIX or if the shell type is unknown)).

Definition at line 325 of file pm_sysShell.F90.

is

type(shellis_type) pm_sysShell::shell_type::is

The scalar object of type shellis_type whose logical components indicate the shell name.

Definition at line 322 of file pm_sysShell.F90.

name

character(:, SK), allocatable pm_sysShell::shell_type::name

The allocatable scalar character containing the name of or path to the current shell.

Definition at line 326 of file pm_sysShell.F90.

pathsep

character(1, SK) pm_sysShell::shell_type::pathsep = SK_":"

The scalar character of default kind SK of length 1 containing the preferred single-character shell path separator (e.g., ; (Windows) or : (POSIX or if the shell type is unknown)).

Definition at line 324 of file pm_sysShell.F90.

---

The documentation for this type was generated from the following file:

• src/fortran/main/pm_sysShell.F90