It is recommended to use bpf_probe_read_kernel_{str} in the bpf tools.
See kernel commit 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}()
only to archs where they work")

Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>

In the man pages of tcplife and tcpstates, the name of the field for
the remote port and address (DPORT, DADDR) differs from the tool
itself (RPORT, RADDR). This patch fix the man pages.

The man page of tcpdrop mentions options that do not exists. This
patch fix that. It also fix the comment at the head of the code that
too mentions inexistents options.

The man pages for solisten and sofdsnoop are missing. This patch adds
them.

The deadlock_detector tools has been rename simply deadlock, but its
manpage is still named deadlock_detector although its content has been
updated. This patch rename the manpage.

Simplify code following #2198 (https://github.com/iovisor/bcc/pull/2198).

Some tools are not touched: mountsnoop.py, trace.py, lib/*.py, old/*.py.

Handle keyboard interrupt to avoid backtrace printed out when user
presses Ctrl-C. Other tools have been fixed recently. Let's fix these
remaining tools.

* fixed shebangs in tools (and lib)

* fixed shebangs in examples

* do not mangle shebangs in rpm spec

* renamed style-check.sh to c-style-check.sh

* factored out python linter to a separate file

* added shebang validation to the py-style-check

* added shebangs to all python executables

* tools: Add shmsnoop to spy on shm* syscalls

Adding shmsnoop tool to trace System V shared memory
syscalls: shmget, shmat, shmdt, shmctl

  # ./shmsnoop.py
  PID    COMM                SYS              RET ARGs
  19813  server           SHMGET            10000 key: 0x78020001, size: 20, shmflg: 0x3b6 (IPC_CREAT|0666)
  19813  server            SHMAT     7f1cf8b1f000 shmid: 0x10000, shmaddr: 0x0, shmflg: 0x0
  19816  client           SHMGET            10000 key: 0x78020001, size: 20, shmflg: 0x1b6 (0666)
  19816  client            SHMAT     7f4fd8ee7000 shmid: 0x10000, shmaddr: 0x0, shmflg: 0x0
  19816  client            SHMDT                0 shmaddr: 0x7f4fd8ee7000
  19813  server            SHMDT                0 shmaddr: 0x7f1cf8b1f000
  19813  server           SHMCTL                0 shmid: 0x10000, cmd: 0, buf: 0x0

Every call the shm* syscall (SHM column) is displayed
on separate line together with process info (PID/COMM
columns) and argument details: return value (RET column)
and syscall arguments (ARGs column).

The ARGs column contains 'arg: value' couples that represent
given syscall arguments as described in their manpage.

It supports standard options to filter on pid/tid,
to specify duration of the trace and command name
filter, like:

    ./shmsnoop           # trace all shm*() syscalls
    ./shmsnoop -T        # include timestamps
    ./shmsnoop -p 181    # only trace PID 181
    ./shmsnoop -t 123    # only trace TID 123
    ./shmsnoop -d 10     # trace for 10 seconds only
    ./shmsnoop -n main   # only print process names containing "main"

* tools: Add sofdsnoop to spy on fds passed through socket

The sofdsnoop traces FDs passed through unix sockets.

  # ./sofdsnoop
  ACTION TID    COMM             SOCKET                    FD    NAME
  SEND   2576   Web Content      24:socket:[39763]         51    /dev/shm/org.mozilla.ipc.2576.23874
  RECV   2576   Web Content      49:socket:[809997]        51
  SEND   2576   Web Content      24:socket:[39763]         58    N/A
  RECV   2464   Gecko_IOThread   75:socket:[39753]         55

Every file descriptor that is passed via unix sockets os displayed
on separate line together with process info (TID/COMM columns),
ACTION details (SEND/RECV), file descriptor number (FD) and its
translation to file if available (NAME).

examples:
    ./sofdsnoop           # trace file descriptors passes
    ./sofdsnoop -T        # include timestamps
    ./sofdsnoop -p 181    # only trace PID 181
    ./sofdsnoop -t 123    # only trace TID 123
    ./sofdsnoop -d 10     # trace for 10 seconds only
    ./sofdsnoop -n main   # only print process names containing "main"