Messages in this thread Patch in this message | | | Date | Tue, 5 Oct 2004 20:52:14 +0200 | From | Jörn Engel <> | Subject | [PATCH] Console: fall back to /dev/null when no console is availlable |
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Looks pretty trivial, but opinions on this subject may vary. Comments?
Jörn
-- More computing sins are committed in the name of efficiency (without necessarily achieving it) than for any other single reason - including blind stupidity. -- W. A. Wulf
Some userspace applications rely on the assumption that fd's 0, 1 and 2 are always open and function as raw stdin, stdout and stderr, respectively.
With no console registered, init get's called without those fd's already open. Arguably, init should know better, handle that case and fix things before forking other processed. But what about init=/bin/bash? Ok, bash could be fixed as well, as could...
Instead, this patch opens /dev/null when /dev/console doesn't work. It swallows all output and doesn't give much input, but programs can handle that just fine.
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> ---
main.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletion(-)
--- linux-2.6.8cow/init/main.c~console 2004-10-05 20:46:40.000000000 +0200 +++ linux-2.6.8cow/init/main.c 2004-10-05 20:46:08.000000000 +0200 @@ -695,8 +695,11 @@ system_state = SYSTEM_RUNNING; numa_default_policy(); - if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) + if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0) { printk("Warning: unable to open an initial console.\n"); + if (open("/dev/null", O_RDWR, 0) == 0) + printk(" Falling back to /dev/null.\n"); + } (void) sys_dup(0); (void) sys_dup(0); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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