Binary File Support - 5.4.4

Starting in Release 5.4.4 you can open a file with a 'binary' option. In this case, the <read length> tells the API how many characters to read. If you do not pass a <read length> or pass zero, it will default to the length of the <read buffer> field. The <length read> will always tell you how many characters were actually read. If the length of <read_buffer> is greater than 32000, only the first 32000 bytes will be read. The API will return EOF in .STREAM READ when there are no more characters to be read.

Usage: (Option 1)

Usage: (Option 2, 5.3.2 or later only)

Usage: (5.3.1 or earlier)

Usage: (5.3.2 or later)

      PASS         <read_buffer>              FIELD            SHARE? Y
      PASS         <stream_name>              FIELD            SHARE? N
      PASS         <read_length>              FIELD            SHARE? N
      PASS         <length_read>              FIELD            SHARE? Y
      GOSUB    --- .STREAM READ
      *        check for errors
      IF       --- .STREAM READ               NE

<length_read> is the number of characters actually read (5.3.2 and higher only). This must be passed SHARED to return a value.

      PASS         <read_buffer>              FIELD            SHARE? Y
      PASS         <stream_name>              FIELD            SHARE? N
      PASS         <read_length>              FIELD            SHARE? Y

.STREAM READ

This subroutine is called to read a file stream.

Usage:

      PASS         <read_buffer>                               SHARE? Y
      PASS         <stream_name>                               SHARE? N
      PASS         <read_length>                               SHARE? Y
      GOSUB    --- .STREAM READ
      *        check for errors
      IF       --- .STREAM OPEN               NE

Description:

This subroutine is called to read a file stream previously opened for READ access via .STREAM OPEN.

The first two parameters are required, and the subroutine will CANCEL if they are are not all received. The <read_length> parameter is optional.

<read_buffer> identifies the variable into which the data will be read (Required). This subroutine can read lines up to a maximum of 32000 characters. This must be passed SHARED to return any data.

<stream_name> is the name of the previously opened stream (Required).

<read_length> is the number of bytes to read (optional). If not passed, or blank/zero is passed, it will read up until the line termination character specified in .STREAM OPEN. If passed shared, it will return the number of characters actually read, however, you should set it back to zero before the next GOSUB --- .STREAM READ, otherwise this subroutine will only read that number of characters.

This subroutine sets a result value in the corresponding results Token field. The 'Data was truncated' result means the <read_buffer> field you passed was not large enough to contain all the data that was read.

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-- JeanNeron - 2012-01-23