GaryScott wrote:
> On Jul 23, 8:44 am, badger <mdeka...@[EMAIL PROTECTED]
> wrote:
>> On 23 Jul, 08:08, m...@[EMAIL PROTECTED]
wrote:
>>
>>
>>
>>
>>
>>> In a previous article, badger <mdeka...@[EMAIL PROTECTED]
> wrote:
>>>> Hi,
>>>> Im new to fortran and Im trying and (failing) to solve my little
>>>> problem. Any help would be much appreciated?!
>>>> Im trying to read a text header that I have appended to the top of a
>>>> binary file and then read the binary file
>>>> ie.
>>>> 1
>>>> 360
>>>> 720
>>>> 0
>>>> Blah blah blah
>>>> where blah is the start of the binary file.
>>>> I can't seem to work out how to read the binary part - i.e. skip over
>>>> the header bit. So far I have
>>>> PROGRAM read_binary
>>>> IMPLICIT NONE
>>>> INTEGER :: num_rows , num_cols , num_frames , sizeofbyte = 1
>>>> INTEGER, ALLOCATABLE, DIMENSION (:) :: pft
>>>> INTEGER :: junk(10)
>>>> INTEGER :: i, stdin = 10, hdr_length = 4
>>>> INTEGER :: ioerr = 0
>>>> OPEN ( stdin, FILE = '/dev/stdin', STATUS = 'old', ACCESS =
'stream',
>>>> &
>>>> FORM = 'FORMATTED', IOSTAT = ioerr )
>>>> IF ( ioerr /= 0 ) THEN
>>>> PRINT *, "Error opening file"
>>>> STOP
>>>> END IF
>>>> DO i = 1, hdr_length
>>>> READ ( stdin, *, iostat = ioerr ) hdr_stuff(i)
>>>> IF ( ioerr /= 0 ) THEN
>>>> PRINT *, "Error reading file header"
>>>> STOP
>>>> END IF
>>>> END DO
>>>> num_frames = hdr_stuff(1)
>>>> num_rows = hdr_stuff(2)
>>>> num_cols = hdr_stuff(3)
>>>> ALLOCATE ( pft(num_rows * num_cols * num_frames) )
>>>> PRINT *, num_frames
>>>> PRINT *, num_rows
>>>> PRINT *, num_cols
>>>> CLOSE ( stdin, IOSTAT = ioerr )
>>>> IF ( ioerr /= 0 ) THEN
>>>> PRINT *, "Error closing file"
>>>> STOP
>>>> END IF
>>>> OPEN ( stdin, file = '/dev/stdin', form = 'unformatted', access =
>>>> 'direct', &
>>>> recl = sizeofbyte, iostat = ioerr )
>>>> IF ( ioerr /= 0 ) THEN
>>>> PRINT *, "Error opening file for bin"
>>>> STOP
>>>> END IF
>>>> END PROGRAM read_binary
>>>> As I said I think that the way I have approached it thus far is ok -
>>>> open file read header, close file, reopen file and try and read
>>>> binary. Only I have no idea how to read the binary part - I can't
seem
>>>> to skip over the binary bit!!
>>>> Thanks.
>>> Depends what binary means - sometimes that will have record sizes.
>>> Anyway - assuming it is "straight binary" - I.e. you can
>>> read in any amount anytime and not lose anything,
>>> I would suggest reading the header unformatted- as a
>>> array of bytes - which could be equivalenced to a string,
>>> on wbich you could do an internal read.
>>> Chris
>> Thanks - but...
>> As I said and showed in my code - I can read the header bit fine. I
>> then close the file, and reopen it to read the binary (bytes in this
>> case) but I have no idea how to step across the header again when I
>> reopen it and try to read the file as binary?- Hide quoted text -
>>
>> - Show quoted text -
>
> One possible hint: If the header size is fixed (or you otherwise know
> its size), just read it into a dummy/unused variable and discard it
> (define a second header (or reuse the old variable if you're done with
> it or have saved it off) and include it on the "binary" read (assuming
> it represents the proper size).
Isn't there a big oversight here, that UNFORMATTED is not the same as a
raw data
stream? On many systems, UNFORMATTED has codes inserted that describe the
size
of the next bit of data. These codes will be gibberish if you try to read
a
piece of text as UNFORMATTED.
cheers,
Rich
PS Been away for a while... hi everyone!
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