From: ahoward <ahoward@...>
Date: 2003-01-27T02:13:55+09:00
Subject: Re: solaris porting problem -- flock failure?

On Mon, 27 Jan 2003, ts wrote:

> a> does your solaris os have this disclaimer?
>
>  ruby use fcntl()

????

~ > uname -a && ruby -v
Linux eli.fsl.noaa.gov 2.4.2-2 #1 SMP Fri Nov 23 20:51:15 GMT 2001 i686 unknown
ruby 1.6.7 (2002-03-01) [i686-linux]

file.c :

1531 #if defied(EWOULDBLOCK) && 0
1532 static int
1533 rb_thread_flock(fd, op, fptr)
1534     int fd, op;
1535     OpenFile *fptr;
1536 {
1537     if (rb_thread_alone() || (op & LOCK_NB)) {
1538         return flock(fd, op);
1539     }
1540     op |= LOCK_NB;
1541     while (flock(fd, op) < 0) {
1542         switch (errno) {
1543           case EAGAIN:
1544           case EACCES:
1545 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
1546           case EWOULDBLOCK:
1547 #endif
1548             rb_thread_polling();        /* busy wait */
1549             rb_io_check_closed(fptr);
1550             continue;
1551           default:
1552             return -1;
1553         }
1554     }
1555     return 0;
1556 }
1557 #define flock(fd, op) rb_thread_flock(fd, op, fptr)
1558 #endif
1559
1560 static VALUE
1561 rb_file_flock(obj, operation)
1562     VALUE obj;
1563     VALUE operation;
1564 {
1565 #ifndef __CHECKER__
1566     OpenFile *fptr;
1567     int ret;
1568
1569     rb_secure(2);
1570     GetOpenFile(obj, fptr);
1571
1572     if (fptr->mode & FMODE_WRITABLE) {
1573         fflush(GetWriteFile(fptr));
1574     }
1575     TRAP_BEG;
1576     ret = flock(fileno(fptr->f), NUM2INT(operation));
1577     TRAP_END;
1578     if (ret < 0) {
1579         switch (errno) {
1580           case EAGAIN:
1581           case EACCES:
1582 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
1583           case EWOULDBLOCK:
1584 #endif
1585               return Qfalse;
1586         }
1587         rb_sys_fail(fptr->path);
1588     }
1589 #endif
1590     return INT2FIX(0);
1591 }
1592 #undef flock



also, it appears to me (just glancing over sources) that ruby uses
fflush(stream) which only flushes into kernel space and does not guaruntee
data is written to disk *even on file close* !!  eg.  sync must also be used.


-a




-- 

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 | Ara Howard
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