CAPLfunctionIso11783fsreadfile

Open topic with navigation

CAPL Functions » ISO11783 » ISO11783 Node Layer » Iso11783FSReadFile

Iso11783FSReadFile

Valid for: CANoe DE • CANoe4SW DE

Function Syntax

long Iso11783FSReadFile( dword fileHandle, dword bufferSize, char buffer[] );
long Iso11783FSReadFile( dword fileHandle, dword bufferSize, byte buffer[] );
long Iso11783FSReadFile( dword fileHandle, dword bufferSize, char buffer[], long flags);
long Iso11783FSReadFile( dword fileHandle, dword bufferSize, byte buffer[], long flags);

Description

The function reads data from an open file and directory entries from an open directory respectively.

Whenever reading directory entries, ensure that handle consists of at least (n * 22 + 2) bytes (n = the number of directory entries to read passed in size. 22 bytes is a maximum length directory entry when the filename length is 12 characters (subject to the 8.3 naming convention). Two bytes are used for the word in buffer[0] and buffer[1] with the number of directory entries actually read).

Parameters

• fileHandle: File or directory handle, see also Iso11783FSOpenFile

• bufferSize: Size of buffer in Bytes (handle references file) or number of directory entries to read (handle references directory)

• buffer: The read data is copied into this buffer. The word space consisting of buffer[0] (low byte) and buffer[1] (high byte) contains the number of read data bytes from the file (handle references file) or the number of read directory entries (handle references directory) respectively.

  Structure of a directory entry:

  • Byte 1: length (bytes) of the file or directory name
  • Byte 2-n: file or directory name
  • Byte n+1: attributes (see Iso11783GetFileInfo)
  • Bytes n+2, n+3: date
    • bits 1..5: day
    • bits 6..9: month
    • bits 10..16: year-1989
  • Bytes m+4, n+5: time
    • bits 1..5: seconds/2
    • bits 6..11: minutes
    • bits 12..16: hours
  • Bytes n+6..n+9: size of the file/directory

• flags: Bit 0: if this bit is set hidden files are listed during reading directories

Return Values

• ≥ 0: number of bytes written to buffer
• < 0: error code

Example

// Read data from file
LONG handle;
char data[200];

handle = Iso11783FSOpenFile( "\test.TXT", 0x00 );
if (handle > 0) {
  Iso11783FSReadFile( handle, elCount(data), data );
  Iso11783FSCloseFile( handle );
}

// Read directory entries:
LONG handle;
char data[200];

handle = Iso11783FSOpenFile( "\DIR1", 0x03 );
if (handle > 0) {
  Iso11783FSReadFile( handle, (elCount(data)-2)/22, data );
  Iso11783FSCloseFile( handle );
}