PHP fseek() Function

Definition

The fseek() function seeks in an open file, by moving the file pointer from its current position to a new position, forward or backward, specified by the number of bytes.

Syntax

PHP fseek() Function has the following syntax.

Parameter

Possible values for whence:

• SEEK_SET - Set position equal to offset. Default
• SEEK_CUR - Set position to current location plus offset
• SEEK_END - Set position to EOF plus offset to move to a position before EOF, the offset must be a negative value

Return

This function returns 0 on success, or -1 on failure. Seeking past EOF will not generate an error.

Example

fseek() moves a file handle pointer to an arbitrary position.

<?PHP/* www. ja  v a2  s .  co  m*/
      $filename = "c:/abc/test.txt";
      $handle = fopen($filename, "w+");
      fwrite($handle, "java2s.com\n");
      rewind($handle);
      fseek($handle, 1);
      fwrite($handle, "o");
      fseek($handle, 2, SEEK_CUR);
      fwrite($handle, "e");
      fclose($handle);
?>

The first byte of a file is byte 0, and you count upward from there. The second byte is at index 1, the third at index 2, etc.

Find the current position by using ftell().