FSETPOS(3)                 POSIX Programmer's Manual                FSETPOS(3)



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

NNAAMMEE
       fsetpos -- set current file position

SSYYNNOOPPSSIISS
       #include <stdio.h>

       int fsetpos(FILE *_s_t_r_e_a_m, const fpos_t *_p_o_s);

DDEESSCCRRIIPPTTIIOONN
       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.1-2017
       defers to the ISO C standard.

       The _f_s_e_t_p_o_s() function shall set the file position and state indicators
       for the stream pointed to by _s_t_r_e_a_m according to the value of the
       object pointed to by _p_o_s, which the application shall ensure is a value
       obtained from an earlier call to _f_g_e_t_p_o_s() on the same stream. If a
       read or write error occurs, the error indicator for the stream shall be
       set and _f_s_e_t_p_o_s() fails.

       A successful call to the _f_s_e_t_p_o_s() function shall clear the end-of-file
       indicator for the stream and undo any effects of _u_n_g_e_t_c() on the same
       stream. After an _f_s_e_t_p_o_s() call, the next operation on an update stream
       may be either input or output.

       The behavior of _f_s_e_t_p_o_s() on devices which are incapable of seeking is
       implementation-defined.  The value of the file offset associated with
       such a device is undefined.

       The _f_s_e_t_p_o_s() function shall not change the setting of _e_r_r_n_o if
       successful.

RREETTUURRNN VVAALLUUEE
       The _f_s_e_t_p_o_s() function shall return 0 if it succeeds; otherwise, it
       shall return a non-zero value and set _e_r_r_n_o to indicate the error.

EERRRROORRSS
       The _f_s_e_t_p_o_s() function shall fail if, either the _s_t_r_e_a_m is unbuffered
       or the _s_t_r_e_a_m's buffer needed to be flushed, and the call to _f_s_e_t_p_o_s()
       causes an underlying _l_s_e_e_k() or _w_r_i_t_e() to be invoked, and:

       EEAAGGAAIINN The O_NONBLOCK flag is set for the file descriptor and the
              thread would be delayed in the write operation.

       EEBBAADDFF  The file descriptor underlying the stream file is not open for
              writing or the stream's buffer needed to be flushed and the file
              is not open.

       EEFFBBIIGG  An attempt was made to write a file that exceeds the maximum
              file size.

       EEFFBBIIGG  An attempt was made to write a file that exceeds the file size
              limit of the process.

       EEFFBBIIGG  The file is a regular file and an attempt was made to write at
              or beyond the offset maximum associated with the corresponding
              stream.

       EEIINNTTRR  The write operation was terminated due to the receipt of a
              signal, and no data was transferred.

       EEIIOO    A physical I/O error has occurred, or the process is a member of
              a background process group attempting to perform a _w_r_i_t_e() to
              its controlling terminal, TOSTOP is set, the calling thread is
              not blocking SIGTTOU, the process is not ignoring SIGTTOU, and
              the process group of the process is orphaned.  This error may
              also be returned under implementation-defined conditions.

       EENNOOSSPPCC There was no free space remaining on the device containing the
              file.

       EEPPIIPPEE  An attempt was made to write to a pipe or FIFO that is not open
              for reading by any process; a SIGPIPE signal shall also be sent
              to the thread.

       EESSPPIIPPEE The file descriptor underlying _s_t_r_e_a_m is associated with a pipe,
              FIFO, or socket.

       The _f_s_e_t_p_o_s() function may fail if:

       EENNXXIIOO  A request was made of a nonexistent device, or the request was
              outside the capabilities of the device.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
       None.

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       None.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _S_e_c_t_i_o_n _2_._5, _S_t_a_n_d_a_r_d _I_/_O _S_t_r_e_a_m_s, _f_o_p_e_n(), _f_t_e_l_l(), _l_s_e_e_k(), _r_e_w_i_n_d(),
       _u_n_g_e_t_c(), _w_r_i_t_e()

       The Base Definitions volume of POSIX.1-2017, <<ssttddiioo..hh>>

CCOOPPYYRRIIGGHHTT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  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.opengroup.org/unix/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                  2017                           FSETPOS(3)
