man3/fpurge.3

   1 '\" t
   2 .\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>.
   3 .\"
   4 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   5 .\"
   6 .TH fpurge 3 (date) "Linux man-pages (unreleased)"
   7 .SH NAME
   8 fpurge, __fpurge \- purge a stream
   9 .SH LIBRARY
  10 Standard C library
  11 .RI ( libc ", " \-lc )
  12 .SH SYNOPSIS
  13 .nf
  14 /* unsupported */
  15 .B #include <stdio.h>
  16 .PP
  17 .BI "int fpurge(FILE *" stream );
  18 .PP
  19 /* supported */
  20 .B #include <stdio.h>
  21 .B #include <stdio_ext.h>
  22 .PP
  23 .BI "void  __fpurge(FILE *" stream );
  24 .fi
  25 .SH DESCRIPTION
  26 The function
  27 .BR fpurge ()
  28 clears the buffers of the given stream.
  29 For output streams this discards any unwritten output.
  30 For input streams this discards any input read from the underlying object
  31 but not yet obtained via
  32 .BR getc (3);
  33 this includes any text pushed back via
  34 .BR ungetc (3).
  35 See also
  36 .BR fflush (3).
  37 .PP
  38 The function
  39 .BR __fpurge ()
  40 does precisely the same, but without returning a value.
  41 .SH RETURN VALUE
  42 Upon successful completion
  43 .BR fpurge ()
  44 returns 0.
  45 On error, it returns \-1 and sets
  46 .I errno
  47 to indicate the error.
  48 .SH ERRORS
  49 .TP
  50 .B EBADF
  51 .I stream
  52 is not an open stream.
  53 .SH ATTRIBUTES
  54 For an explanation of the terms used in this section, see
  55 .BR attributes (7).
  56 .TS
  57 allbox;
  58 lbx lb lb
  59 l l l.
  60 Interface       Attribute       Value
  61 T{
  62 .na
  63 .nh
  64 .BR __fpurge ()
  65 T}      Thread safety   MT-Safe race:stream
  66 .TE
  67 .sp 1
  68 .SH STANDARDS
  69 None.
  70 .SH HISTORY
  71 .TP
  72 .BR fpurge ()
  73 4.4BSD.
  74 Not available under Linux.
  75 .TP
  76 .BR __fpurge ()
  77 Solaris, glibc 2.1.95.
  78 .SH NOTES
  79 Usually it is a mistake to want to discard input buffers.
  80 .SH SEE ALSO
  81 .\" .BR fclean (3),
  82 .BR fflush (3),
  83 .BR setbuf (3),
  84 .BR stdio_ext (3)