fpurge(3)		    Library Functions Manual		       fpurge(3)

NAME
     fpurge, __fpurge - purge a stream

LIBRARY
     Standard C library (libc, -lc)

SYNOPSIS
     /* unsupported */
     #include <stdio.h>

     int fpurge(FILE *stream);

     /* supported */
     #include <stdio.h>
     #include <stdio_ext.h>

     void  __fpurge(FILE *stream);

DESCRIPTION
     The  function  fpurge() clears the buffers of the given stream.  For output
     streams this discards any unwritten output.  For input  streams  this  dis-
     cards  any	 input	read from the underlying object but not yet obtained via
     getc(3); this includes any	 text  pushed  back  via  ungetc(3).   See  also
     fflush(3).

     The  function  __fpurge()	does precisely the same, but without returning a
     value.

RETURN VALUE
     Upon successful completion fpurge() returns 0.  On error, it returns -1 and
     sets errno to indicate the error.

ERRORS
     EBADF  stream is not an open stream.

ATTRIBUTES
     For an explanation of the terms used in this  section,  see  attributes(7).
     allbox; lbx lb lb l l l.  Interface Attribute Value T{ __fpurge()
     T}	  Thread safety	  MT-Safe race:stream

STANDARDS
     None.

HISTORY
     fpurge()
	    4.4BSD.  Not available under Linux.

     __fpurge()
	    Solaris, glibc 2.1.95.

NOTES
     Usually it is a mistake to want to discard input buffers.

SEE ALSO
     fflush(3), setbuf(3), stdio_ext(3)

Linux man-pages 6.18		   2026-02-08			       fpurge(3)