@FILESEEKL

@FILESEEKL[n,line]:  Moves the file pointer to the specified line in the 
file whose handle is n.  The first line in the file is numbered 0. 
 Returns the new position of the pointer, in bytes from the start of the 
file.  Be sure to read the cautionary note about file functions under 
Variable Functions. 

@FILESEEKL must read each line of the file up to the target line in order 
to position the pointer, and will therefore cause significant delays if 
used in a long loop or on a large file.