Common bash script

====== pattern with ls commands -- need further study ======
<file>
ls -1FA | grep \/ | sed -e "s/\// /g" -e "/CVS/d" -e "/include/d" -e "/.svn/d"
</file>
====== extract mac address ======

method 1: ifconfig eth0 | awk '/HWaddr/ {print $5}'

method 2: ifconfig eth0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}' 

Note
<nowiki>
  The -o will cause grep to only print the part of the line that matches the expression.
   [[:xdigit:]]{1,2} will match 1 or 2 hexidecimal digits (Solaris doesn't output leading zeros).
</nowiki>   

====== Change string1 to sing2 in all files in current folder ====== 
<file bash replace_string_file.sh>
for f in *
do
    sed 's/string1/string2/g' $f > $f.new &&
    mv $f.new $f
done
</file>

====== wirte multiple line to one file ====== 

<file bash cat_example.sh>
cat >/var/test << "EOF"
plugin /lib/pppd/2.4.4/pppoatm.so
user test
password test
lcp-echo-interval 10
EOF 

</file>

====== change Dec value to Hex value ====== 
<file bash dec_hex.sh>
a=100 
b=`printf "0x%x", $a`
echo $b
</file>

====== Display softlink as specified ====== 
===  Display all softlink under current folder ====

find ./ -type l

=== Display all softlink and ls or file ====

find ./ -type l -exec ls -l {} \;<br />find ./ -type l | xargs file

=== Display all softlink which link to a directory only ===

for f in $(find ./ -type l); do if [ -d "$f" ]; then ls -al "$f"; fi; done

===  Display all softlink which link to a file ===

for f in $(find ./ -type l); do if [ -f "$f" ]; then ls -al "$f"; fi; done

=== Display all broken softlink ===

find ./ -type l | while read f; do if [ ! -e "$f" ]; then ls -l "$f"; fi; done

=== link a directory to another directory ===

ln -s xxxx -T /home/yyy/zzz ( link current directoryxxxx to /home/yyy/zzz also changed xxxx to zzz)

=== link a file to another directory's file ===

ln -s xxxx -t /home/yyy/ ( link current file xxxx to /home/yyy/xxxx)

====  print directory tree ==== 

tree -d