input-stream — an input stream designator. The default is standard input.

eof-error-p — a generalized boolean. The default is true.

eof-value — an object. The default is nil.

recursive-p — a generalized boolean. The default is false.

line — a string or the eof-value.

missing-newline-p — a generalized boolean.

Reads from input-stream a line of text that is terminated by a newline or end of file.

If recursive-p is true, this call is expected to be embedded in a higher-level call to read or a similar function used by the Lisp reader.

The primary value, line, is the line that is read, represented as a string (without the trailing newline, if any). If eof-error-p is false and the end of file for input-stream is reached before any characters are read, eof-value is returned as the line.

The secondary value, missing-newline-p, is a generalized boolean that is false if the line was terminated by a newline, or true if the line was terminated by the end of file for input-stream (or if the line is the eof-value).

 (setq a "line 1 
 line2") 
→ "line 1 
 line2" 
 (read-line (setq input-stream (make-string-input-stream a))) 
→ "line 1", false 
 (read-line input-stream) 
→ "line2", true 
 (read-line input-stream nil nil) 
→ NIL, true

*standard-input*, *terminal-io*.

If an end of file₂ occurs before any characters are read in the line, an error is signaled if eof-error-p is true.

read

The corresponding output function is write-line.