fpurge(3) — Linux manual page

fpurge(3)                Library Functions Manual               fpurge(3)

NAME         top

       fpurge, __fpurge - purge a stream

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       int fpurge(FILE *stream);

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

       void  __fpurge(FILE *stream);

DESCRIPTION         top

       The function fpurge() clears the buffers of the given stream.  For
       output streams this discards any unwritten output.  For input
       streams this discards 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         top

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

ERRORS         top

       EBADF  stream is not an open stream.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────┬───────────────┬─────────────────────┐
       │ Interface                │ Attribute     │ Value               │
       ├──────────────────────────┼───────────────┼─────────────────────┤
       │ __fpurge()               │ Thread safety │ MT-Safe race:stream │
       └──────────────────────────┴───────────────┴─────────────────────┘

STANDARDS         top

       None.

HISTORY         top

       fpurge()
              4.4BSD.  Not available under Linux.

       __fpurge()
              Solaris, glibc 2.1.95.

NOTES         top

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

SEE ALSO         top

       fflush(3), setbuf(3), stdio_ext(3)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
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Linux man-pages 6.15            2025-05-17                      fpurge(3)

Pages that refer to this page: fflush(3),  stdio(3),  stdio_ext(3)

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