Solaris

# In the beginning it's good to create a temp directory temp_dir that will contain only the gzipped files.

mkdir /home/temp_dir

cd /home/mmc
for i in `ls | xargs file | awk -F: '! /gzip/{print $1}'`
do
gzip $i
mv $i".gz" /home/temp_dir/
done

# Now cd to temp_dir to remove extension gz from files just created 

cd /home/temp_dir
for i in `ls`
do
mv $i "$(basename $i .gz)"
done

# Now if you need the just created files to be moved to your specific directory say /home/ttc, while you are still at /home/temp_dir do a mv

mv * /home/ttc

ls | xargs file | awk -F: '! /gzip/{print $1}'

ls | xargs file --> list files and execute the file command ( to find out the file type)
awk -F: '! /gzip/{print $1}' --> from the results give me only the files that are not zipped, ( ! /gzip/).

$ gzip -t blah

gzip: blah: not in gzip format

$ gzip -t blah 2>/dev/null
$