Shell Programming and Scripting

[root@inerdtech control]# sh -vx ./anticrash.sh
#!/bin/sh

+ $'\r'
: command not founde 2:
while true
do
  rm banme.tmp
  :> banme.txt
  /usr/sbin/tcpdump -p -c 100 -n -i eth0 "dst host 75.127.119.54 and udp port 7777" >banme.tmp
  grep "length 0" banme.tmp | cut -f 3 -d " " | cut -f 1-4 -d "." >> banme.txt
  if [ `grep -c . banme.txt` -gt 0 ]
  then
    ip=`head -1 banme.txt`
    if [ `grep -c ${ip} /etc/sysconfig/iptables` -eq 0 ]
    then
      dat=`date`
      echo "${dat} adding ${ip} to iptables" >> banme.log
      /sbin/iptables -A INPUT -s ${ip} -j DROP
      /sbin/iptables-save > /etc/sysconfig/iptables
    else
      echo "${ip} is already in iptables"
    fi   #//LINE20
./anticrash.sh: line 20: syntax error near unexpected token `fi'
'/anticrash.sh: line 20: `    fi   #//LINE20
[root@inerdtech control]#

tr -d '\r' < your_file > new_file

> cat -v ctrlM.sh
#/usr/bin/bash

# Next line is ctrl-M
^M
date
> sh -vx ctrlM.sh
#/usr/bin/bash

# Next line is ctrl-M

+ $'\r'
ctrlM.sh: line 4: $'\r': command not found
date
+ date
Sun Jul 27 22:34:29     2008
>

> tr -d '\r' <ctrlM.sh >no_ctrlM.sh
> sh -vx no_ctrlM.sh
#/usr/bin/bash

# Next line is ctrl-M

date
+ date
Sun Jul 27 22:37:49     2008
>

# way  number 1
dos2ux anticrash.sh > tmfile; mv tmfile anticrash.sh; chmod +x anticrash.sh
#way number 2
tr -d '\r' < aniticrash.sh > newanticrash.sh; chmod +x newanticrash.sh

# note '\r' is the return button or ^M