The gzrewind() function shall set the starting position for the next read on compressed file stream file to the beginning of file. file must be open for reading.
gzrewind() is equivalent to
(int)gzseek(file, 0L, SEEK_SET)
On success, gzrewind() shall return 0. On error, gzrewind() shall return -1, and may set the error value for file accordingly.
On error, gzrewind() shall return
indicating that file is
NULL, or does not represent
an open compressed file stream, or represents a compressed file stream
that is open for writing and is not currently at the beginning of file.