NAME

       opensnoop.bt - Trace open() syscalls. Uses bpftrace/eBPF.

SYNOPSIS

       opensnoop.bt

DESCRIPTION

       opensnoop  traces the open() syscall, showing which processes are attempting to open which
       files. This can be useful for determining the location of config and  log  files,  or  for
       troubleshooting applications that are failing, specially on startup.

       This works by tracing the open() syscall tracepoint.

       Since this uses BPF, only the root user can use this tool.

REQUIREMENTS

       CONFIG_BPF and bcc.

EXAMPLES

       Trace all open() syscalls:
              # opensnoop.bt

FIELDS

       PID Process ID

       TID    Thread ID

       COMM   Process name

       FD     File descriptor (if success), or -1 (if failed)

       ERR    Error number (see the system's errno.h)

       PATH   Open path

OVERHEAD

       This  traces  the open tracepoint and prints output for each event. As the rate of this is
       generally expected to be low (< 1000/s), the overhead is also expected to  be  negligible.
       If  you  have  an  application  that  is  calling  a  high  rate of open()s, then test and
       understand overhead before use.

SOURCE

       This is from bpftrace.

              https://github.com/iovisor/bpftrace

       Also look in the bpftrace distribution  for  a  companion  _examples.txt  file  containing
       example usage, output, and commentary for this tool.

       This is a bpftrace version of the bcc tool of the same name. The bcc tool may provide more
       options and customizations.

              https://github.com/iovisor/bcc

OS

       Linux

STABILITY

       Unstable - in development.

AUTHOR

       Brendan Gregg

SEE ALSO

       statsnoop.bt(8), execsnoop.bt(8)