fseek, ftell - reposition a file on a logical unit
integer function fseek (lunit, offset, from)
integer offset, from
integer function ftell (lunit)
lunit must refer to an open logical unit. offset is an offset in bytes relative to the position specified by from. Valid values for from
0 meaning `beginning of the file'
1 meaning `the current position'
2 meaning `the end of the file'
The value returned by fseek will be 0 if successful, a system error code otherwise. (See perror(3F))
Ftell returns the current position of the file associated with the specified logical unit. The value is an offset, in bytes, from the
beginning of the file. If the value returned is negative, it indicates an error and will be the negation of the system error code. (See
SEE ALSO fseek(3S), perror(3F)4.2 Berkeley Distribution May 27, 1986 FSEEK(3F)
Check Out this Related Man Page
FSEEK(3) Linux Programmer's Manual FSEEK(3)NAME
fgetpos, fseek, fsetpos, ftell, rewind - reposition a stream
int fseek(FILE *stream, long offset, int whence);
long ftell(FILE *stream);
void rewind(FILE *stream);
int fgetpos(FILE *stream, fpos_t *pos);
int fsetpos(FILE *stream, fpos_t *pos);
The fseek function sets the file position indicator for the stream pointed to by stream. The new position, measured in bytes, is obtained
by adding offset bytes to the position specified by whence. If whence is set to SEEK_SET, SEEK_CUR, or SEEK_END, the offset is relative to
the start of the file, the current position indicator, or end-of-file, respectively. A successful call to the fseek function clears the
end-of-file indicator for the stream and undoes any effects of the ungetc(3) function on the same stream.
The ftell function obtains the current value of the file position indicator for the stream pointed to by stream.
The rewind function sets the file position indicator for the stream pointed to by stream to the beginning of the file. It is equivalent
(void)fseek(stream, 0L, SEEK_SET)
except that the error indicator for the stream is also cleared (see clearerr(3)).
The fgetpos and fsetpos functions are alternate interfaces equivalent to ftell and fseek (with whence set to SEEK_SET), setting and storing
the current value of the file offset into or from the object referenced by pos. On some non-UNIX systems an fpos_t object may be a complex
object and these routines may be the only way to portably reposition a text stream.
The rewind function returns no value. Upon successful completion, fgetpos, fseek, fsetpos return 0, and ftell returns the current offset.
Otherwise, -1 is returned and the global variable errno is set to indicate the error.
EBADF The stream specified is not a seekable stream.
EINVAL The whence argument to fseek was not SEEK_SET, SEEK_END, or SEEK_CUR.
The function fgetpos, fseek, fsetpos, and ftell may also fail and set errno for any of the errors specified for the routines fflush(3),
fstat(2), lseek(2), and malloc(3).
The fgetpos, fsetpos, fseek, ftell, and rewind functions conform to ANSI X3.159-1989 (``ANSI C'').
SEE ALSO lseek(2), fseeko(3)BSD MANPAGE 1993-11-29 FSEEK(3)