How to write output to a string in fortran? - fortran

Question

I need to write a formated output to a string DTSTR. It use to work under layhe fortran but not gfortran
INTEGER*2 MON,DAY,YEAR,HR,MINUTE,SEC,HUND
CHARACTER DY*2
CHARACTER DTSTR*24
COMMON /RD/ DTSTR
...
...
WRITE(DTSTR,10)MON,DAY,YEAR,HR,MINUTE,DY,' ]'
10 FORMAT('[ ',I2,'-',I2.2,'-',I4,2X,I2,':',I2.2,1X,2A2)
it empty just a empty line. If i use following it correctly output. But i want to store this string. Is it possible to do that with gnu fortran.
WRITE(*,10)MON,DAY,YEAR,HR,MINUTE,DY,' ]'
update
I am trying to compile following file. I think the problem might be with the COMMON.
PROGRAM HELO
CALL DOTIME
WRITE(*,5700)DTSTR
5700 FORMAT(24X,A24/)
END
SUBROUTINE DOTIME
C
IMPLICIT NONE
INTEGER*2 MON,DAY,YEAR,HR,MINUTE,SEC,HUND
CHARACTER DY*2
CHARACTER DTSTR*24
COMMON /RD/ DTSTR
integer values(8)
call date_and_time(VALUES=values)
YEAR = values(1)
MON = values(2)
DAY = values(3)
HR = values(5)
MINUTE = values(6)
SEC = values(7)
HUND = values(8)
C =================================================
C
C Incompitable function => CALL GETDAT(YEAR,MON,DAY)
C Incompitable function => GETTIM(HR,MINUTE,SEC,HUND)
IF(HR .GE. 12)THEN
IF(HR .NE. 12)HR=HR-12
DY='PM'
ELSE
DY='AM'
ENDIF
WRITE(DTSTR,10)MON,DAY,YEAR,HR,MINUTE,DY,' ]'
10 FORMAT('[ ',I2,'-',I2.2,'-',I4,2X,I2,':',I2.2,1X,2A2)
RETURN
END

Answer 1

Hmm? It works just fine for me:
program testwrite
implicit none
INTEGER :: MON,DAY,YEAR,HR,MINUTE,SEC,HUND
CHARACTER(LEN=2) :: DY
CHARACTER(LEN=24) :: DTSTR
MON = 4
DAY = 27
YEAR= 2010
HR = 13
MINUTE = 27
SEC = 0
HUND = 0
DY ='WE'
WRITE(DTSTR,10)MON,DAY,YEAR,HR,MINUTE,DY,' ]'
10 FORMAT('[ ',I2,'-',I2.2,'-',I4,2X,I2,':',I2.2,1X,2A2)
print *,'<',trim(DTSTR),'>'
end program testwrite
gives
<[ 4-27-2010 13:27 WE ]>
just as one would expect. Works with several versions of gfortran I have kicking around.
Update: Yes, the problem is in your common block. The common block isn't declared in the main program. But really, it's much simpler and much, much better practice just to pass the string as an argument:
PROGRAM HELO
IMPLICIT NONE
CHARACTER(LEN=24) :: DTSTR
CALL DOTIME(DTSTR)
WRITE(*,5700)DTSTR
5700 FORMAT(24X,A24/)
END
SUBROUTINE DOTIME(DTSTR)
C
IMPLICIT NONE
INTEGER*2 MON,DAY,YEAR,HR,MINUTE,SEC,HUND
CHARACTER DY*2
CHARACTER(LEN=24), INTENT(OUT) :: DTSTR