1. grep -cvP ‘\S’ file
    -P ‘\S'(perl regex) will match any line contains non-space
    -v select non-matching lines
    -c print a count of matching lines

  2. command for check which service are allow to tcp wraper?

    ldd /path/to/binary | grep libwrap.so

    which service are allowed in tcp wrapper and how to find?
    whereis sshd
    sshd: /usr/sbin/sshd /usr/share/man/man8/sshd.8.gz

Leave a Reply

Your email address will not be published.