PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

SETBUF(3P)                POSIX Programmer's Manual               SETBUF(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       setbuf — assign buffering to a stream

SYNOPSIS         top

       #include <stdio.h>

       void setbuf(FILE *restrict stream, char *restrict buf);

DESCRIPTION         top

       The functionality described on this reference page is aligned with
       the ISO C standard. Any conflict between the requirements described
       here and the ISO C standard is unintentional. This volume of
       POSIX.1‐2008 defers to the ISO C standard.

       Except that it returns no value, the function call:

           setbuf(stream, buf)

       shall be equivalent to:

           setvbuf(stream, buf, _IOFBF, BUFSIZ)

       if buf is not a null pointer, or to:

           setvbuf(stream, buf, _IONBF, BUFSIZ)

       if buf is a null pointer.

RETURN VALUE         top

       The setbuf() function shall not return a value.

ERRORS         top

       Although the setvbuf() interface may set errno in defined ways, the
       value of errno after a call to setbuf() is unspecified.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       A common source of error is allocating buffer space as an
       ``automatic'' variable in a code block, and then failing to close the
       stream in the same block.

       With setbuf(), allocating a buffer of BUFSIZ bytes does not
       necessarily imply that all of BUFSIZ bytes are used for the buffer
       area.

       Since errno is not required to be unchanged on success, in order to
       correctly detect and possibly recover from errors, applications
       should use setvbuf() instead of setbuf().

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       Section 2.5, Standard I/O Streams, fopen(3p), setvbuf(3p)

       The Base Definitions volume of POSIX.1‐2008, stdio.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) In the event of any discrepancy between this version and
       the original IEEE and The Open Group Standard, the original IEEE and
       The Open Group Standard is the referee document. The original
       Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                          SETBUF(3P)