# fsetpos

## PROLOG



           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



           fsetpos — set current file position
    


## SYNOPSIS



           #include <stdio.h>
    
           int fsetpos(FILE *_stream_ , const fpos_t *_pos_);
    


## DESCRIPTION



           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 _fsetpos_() function shall set the file position and state
           indicators for the stream pointed to by _stream_ according to the
           value of the object pointed to by _pos_ , which the application shall
           ensure is a value obtained from an earlier call to _fgetpos_() on
           the same stream. If a read or write error occurs, the error
           indicator for the stream shall be set and _fsetpos_() fails.
    
           A successful call to the _fsetpos_() function shall clear the end-
           of-file indicator for the stream and undo any effects of _ungetc_()
           on the same stream. After an _fsetpos_() call, the next operation on
           an update stream may be either input or output.
    
           The behavior of _fsetpos_() on devices which are incapable of
           seeking is implementation-defined.  The value of the file offset
           associated with such a device is undefined.
    
           The _fsetpos_() function shall not change the setting of _errno_ if
           successful.
    


## RETURN VALUE



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


## ERRORS



           The _fsetpos_() function shall fail if, either the _stream_ is
           unbuffered or the _stream_ 's buffer needed to be flushed, and the
           call to _fsetpos_() causes an underlying _lseek_() or _write_() to be
           invoked, and:
    
           **EAGAIN** The O_NONBLOCK flag is set for the file descriptor and the
                  thread would be delayed in the write operation.
    
           **EBADF** 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.
    
           **EFBIG** An attempt was made to write a file that exceeds the
                  maximum file size.
    
           **EFBIG** An attempt was made to write a file that exceeds the file
                  size limit of the process.
    
           **EFBIG** The file is a regular file and an attempt was made to write
                  at or beyond the offset maximum associated with the
                  corresponding stream.
    
           **EINTR** The write operation was terminated due to the receipt of a
                  signal, and no data was transferred.
    
           **EIO** A physical I/O error has occurred, or the process is a
                  member of a background process group attempting to perform
                  a _write_() 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.
    
           **ENOSPC** There was no free space remaining on the device containing
                  the file.
    
           **EPIPE** 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.
    
           **ESPIPE** The file descriptor underlying _stream_ is associated with a
                  pipe, FIFO, or socket.
    
           The _fsetpos_() function may fail if:
    
           **ENXIO** A request was made of a nonexistent device, or the request
                  was outside the capabilities of the device.
    
           _The following sections are informative._
    


## EXAMPLES



           None.
    


## APPLICATION USAGE



           None.
    


## RATIONALE



           None.
    


## FUTURE DIRECTIONS



           None.
    


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