1opensnoop(8) System Manager's Manual opensnoop(8)
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6 opensnoop.bt - Trace open() syscalls. Uses bpftrace/eBPF.
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9 opensnoop.bt
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12 opensnoop traces the open() syscall, showing which processes are
13 attempting to open which files. This can be useful for determining the
14 location of config and log files, or for troubleshooting applications
15 that are failing, specially on startup.
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17 This works by tracing the open() syscall tracepoint.
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19 Since this uses BPF, only the root user can use this tool.
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22 CONFIG_BPF and bcc.
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25 Trace all open() syscalls:
26 # opensnoop.bt
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29 PID Process ID
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31 TID Thread ID
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33 COMM Process name
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35 FD File descriptor (if success), or -1 (if failed)
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37 ERR Error number (see the system's errno.h)
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39 PATH Open path
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42 This traces the open tracepoint and prints output for each event. As
43 the rate of this is generally expected to be low (< 1000/s), the over‐
44 head is also expected to be negligible. If you have an application that
45 is calling a high rate of open()s, then test and understand overhead
46 before use.
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49 This is from bpftrace.
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51 https://github.com/iovisor/bpftrace
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53 Also look in the bpftrace distribution for a companion _examples.txt
54 file containing example usage, output, and commentary for this tool.
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56 This is a bpftrace version of the bcc tool of the same name. The bcc
57 tool may provide more options and customizations.
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59 https://github.com/iovisor/bcc
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62 Linux
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65 Unstable - in development.
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68 Brendan Gregg
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71 statsnoop(8), execsnoop(8)
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75USER COMMANDS 2018-09-08 opensnoop(8)