fgetpos fseek fseeko fsetpos ftell ftello rewind - reposition a stream
function obtains the current value of the file position indicator for the stream pointed to by Fa stream .
function sets the file position indicator for the stream pointed to by Fa stream to the beginning of the file. It is equivalent to:
(void)fseek(stream, 0L, SEEK_SET)
except that the error indicator for the stream is also cleared (see clearerr(3)).
does not return a value, an application wishing to detect errors should clear errno then call rewind (,);
and if errno is non-zero, assume an error has occurred.
function is identical to fseek (,);
except it takes an Fa off_t argument instead of a Fa long . Likewise, the ftello ();
function is identical to ftell (,);
except it returns an Fa off_t .
and fsetpos ();
functions are alternate interfaces for retrieving and setting the current position in the file, similar to ftell ();
and fseek (,);
except that the current position is stored in an opaque object of type Vt fpos_t pointed to by Fa pos . These functions provide a portable way to seek to offsets larger than those that can be represented by a Vt long int . They may also store additional state information in the Vt fpos_t object to facilitate seeking within files containing multibyte characters with state-dependent encodings. Although Vt fpos_t has traditionally been an integral type, applications cannot assume that it is; in particular, they must not perform arithmetic on objects of this type.
If the stream is a wide character stream (see fwide(3)), the position specified by the combination of Fa offset and Fa whence must contain the first byte of a multibyte sequence.
Rv -std fgetpos fseek fseeko fsetpos
Upon successful completion,
and ftello ();
return the current offset. Otherwise, -1 is returned and the global variable errno is set to indicate the error.
and rewind ();
may also fail and set errno for any of the errors specified for the routines fflush(3), fstat(2), lseek(2), and malloc(3).
and ftello ();
functions conform to St -p1003.1-2001 .
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Created 1996-2023 by Maxim Chirkov
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