164  Pascal Report  IdentifiedVariable  =  PointerVariable  'j" .  PointerVariable  =  Variable.  An access to an identified varia )Ie implies an access to the pointer  variable, at which time it is an errol  if  the pointer variable is undefined  or has the value nil. It is an errol  if an identifying pointer value is  destroyed when a reference to the variable that the value identifies  exists.  Examples of identified variables:  A file variable is a variable that  poss,_~sses  a file type. Every file variable  is associated with a so-called buffer variable.  BufferVariable  =  FileVariable  "I" .  FileVariable  =  Variable.  7.4.  Buffer Variables  pl1  pll.Fatherj  pll.Friends1'1'  If  the file variable possesses the type Text, then the buffer variable  possesses the type Char; otherwise the buffer variable possesses the  component type of the file type p( Issessed by the file variable. The  buffer variable is  used to access the current component of the file  variable.  It  is an error to perform an) operation that alters the sequence,  position, or mode of a file variabl: when a reference to the buffer  variable exists. An access or refere, Ice to a buffer variable implies an  access or reference to the associatel! file variable.  Predeclared procedures and fum! ions that manipulate file variables  are described in Sections 11.4,  11.5  aud 12.  When eoln  (F)  becomes true  j  )f  textfile F  (Section 11.5.2), the  buffer variable  FI becomes the char value space (,  '). Thus eoln (F)  is the only way to detect an end-of line marker on F.  Examples of buffer variables:  Inputl  PlI.Friendsl  Pll.Friendsll.Childrenl 