demo_M_process.f90

     program demo_M_process
      use M_process ,only : process_open_write, process_writeline
      use M_process ,only : streampointer, process_close
      implicit none
      ! C file pointer returned by process_open()
      type(streampointer) :: fp
      ! check status of calls to process module routines
      integer :: ierr
      character(len=:),allocatable :: text(:)

      ! open process to write to (ie. start gnuplot(1) program)
      !!call process_open_write('cat',fp,ierr)
      ! open process to write to (ie. start gnuplot(1) program)
      call process_open_write('bash',fp,ierr)

      text=[character(len=128) :: &
      "rm -f sqlite1.db", &
      "sqlite3 sqlite1.db <<\EOF", &
      "-- ***********************************************",&
      "CREATE TABLE IF NOT EXISTS animals(               ",&
      "   name        TEXT   NOT NULL   PRIMARY KEY ,    ",&
      "   hair        INT    NOT NULL   ,                ",&
      "   mobility    INT    NOT NULL   ,                ",&
      "   vision      INT    NOT NULL   );               ",&
      "-- ***********************************************",&
      "INSERT INTO animals(&
      &name,hair,mobility,vision) VALUES('kittens',4,5,1);",&
      "INSERT INTO animals(&
      &name,hair,mobility,vision) VALUES('mice'   ,6,7,2);",&
      "INSERT INTO animals(&
      &name,hair,mobility,vision) VALUES('rats'   ,2,3,3);",&
      "-- ***********************************************",&
      ".quit", &
      "EOF", &
      "##################################################",&
      "sqlite3 -header -column sqlite1.db  'select * from animals'",&
      "sqlite3 sqlite1.db  &
      &'select name, hair, mobility, vision from animals'",&
      "##################################################",&
      "gnuplot --persist <<\EOF                          ",&
      "########################################          ",&
      "#set terminal gif                                 ",&
      "#set output 'M_process.3.gif'                     ",&
      "########################################          ",&
      "#set terminal png                                 ",&
      "#set output 'bar.png'                             ",&
      "########################################          ",&
      "#set terminal pdf enhanced                        ",&
      "#set output 'bar.pdf'                             ",&
      "########################################          ",&
      "#set style data lines                             ",&
      "########################################          ",&
      "set datafile separator ""|""                      ",&
      "set style data histogram                          ",&
      "set style histogram cluster gap 1                 ",&
      "set style fill solid border rgb ""black""         ",&
      "set auto x                                        ",&
      "set yrange [0:*]                                  ",&
      "plot ""< sqlite3 sqlite1.db  &
      &'select name, hair, mobility, vision  from animals'"" \  ", &
      "      using 2:xtic(1) title ""hair"",  \          ",&
      "   '' using 4:xtic(1) title ""vision"", \         ",&
      "   '' using 3:xtic(1) title ""mobility""          ",&
      "quit                                              ",&
      "EOF                                               ",&
      " "]

         !!write(*,'(a)')text
         call process_writeline(text,fp,ierr)
         call process_close(fp,ierr)
         write(*,'(a)')'CLOSED THE PROCESS. RETURNING TO PROGRAM'

      end program demo_M_process