Function: read-positioning-symbols

read-positioning-symbols is a function defined in lread.c.

Signature

(read-positioning-symbols &optional STREAM)

Documentation

Read one Lisp expression as text from STREAM, return as Lisp object.

Convert each occurrence of a symbol into a "symbol with pos" object.

If STREAM is nil, use the value of standard-input (which see). STREAM or the value of standard-input may be:
 a buffer (read from point and advance it)
 a marker (read from where it points and advance it)
 a function (call it with no arguments for each character,
     call it with a char as argument to push a char back)
 a string (takes text from string, starting at the beginning)
 t (read text line using minibuffer and use it, or read from
    standard input in batch mode).

View in manual

Source Code

// Defined in /usr/src/emacs/src/lread.c
{
  if (NILP (stream))
    stream = Vstandard_input;
  if (EQ (stream, Qt))
    stream = Qread_char;
  if (EQ (stream, Qread_char))
    /* FIXME: ?! When is this used !?  */
    return calln (Qread_minibuffer, build_string ("Lisp expression: "));

  return read_internal_start (stream, Qnil, Qnil, true);
}