Append suffix in linux file names with Shell Parameter Expansion

Well, everytime I read about shell (bash) parameter expansion I see examples ripping off the suffixes. But someday, I needed to do the inverse: Append suffixes. How to do that?

I've made a simple bash script to do so:

#!/bin/bash
for i in *; do 
mv ${i} ${i}.sh;
done
exit 0

Using a for loop, I moved every file in the directory to the same name, with a ".sh" appended as suffix.

Feel free to change the suffix you want.

To revert:

#!/bin/bash
for i in *; do
mv ${i} ${i/.sh/};
done
exit 0

In this case, in every file of the directory, ".sh" will be substituted for nothing. It may cause some troubles. Let's suppose you have a dir, full of these files:

1.shellvpower
2.shellvpower
3.shellvpower
4.shellvpower

They'll become:

1ellvpower
2ellvpower
3ellvpower
4ellvpower

So, in a better way, to remove only the suffixes ".sh":

for i in *; do 
mv ${i} ${i%%\.sh};
done
exit 0

Bonus:

Append prefixes:

To append, for instance, prefix "waka":

#!/bin/bash
for i in *; do
mv ${i} ${i/#/waka};
done

Tip: "#" is before "i" (so,  prefix). "%" would be after "i".

It also can be done in a simpler way:

#!/bin/bash
for i in *; do
mv ${i} waka${i};
done

That's all, folks!!