#include	"mail.h"/* Rewind the index file for mail_nextrec(). * Automatically called by mail_open(). * Must be called before first mail_nextrec(). */voidmail_rewind(MAIL *mail){	off_t	offset;	offset = (mail->nhash + 1) * PTR_SZ;		/* +1 for free list ptr */		/* We're just setting the file offset for this process		   to the start of the index records; no need to lock.		   +1 below for newline at end of hash table. */	if ( (mail->idxoff = lseek(mail->idxfd, offset+1, SEEK_SET)) == -1)		err_dump("lseek error");}