20 lines
714 B
Plaintext
20 lines
714 B
Plaintext
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bootlogd: a way to capture all console output during bootup
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in a logfile.
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- bootlogd opens /dev/console and finds out what the real console is
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with an ioctl() if TIOCCONS is available
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- otherwise bootlogd tries to parse /proc/cmdline for console=
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kernel command line arguments
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- then opens the (most probable) real console
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- allocates a pty pair
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- redirects console I/O to the pty pair
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- then goes in a loop reading from the pty, writing to the real
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console and a logfile as soon as a r/w partition is available,
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buffering in memory until then.
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As soon as bootlogd exits or gets killed, the pty is closed and the
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redirection will be automatically undone by the kernel. So that's
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pretty safe.
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