bug reading /proc/sys/kernel/*: only first byte read.

[Michael Tokarev]

I were debugging a weird problem with busybox, and come across
this chunk of strace output:

open("/proc/sys/kernel/osrelease", O_RDONLY) = 3
read(3, "2", 1)                         = 1
read(3, "", 1)                          = 0
close(3)                                = 0

As you can see, after reading one byte from /proc/sys/kernel/osrelease,
next read() returns 0, which is treated as end-of-file by an application.

Why busybox does this single-byte reads is another question (many
shells does that, in order to be able to stop reading at newline).

But this is definitely a bug in kernel, and should be fixed....

It exists in 2.6.17 and 2.6.18

Thanks.

/mjt
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