Answer Posted / shruthi

with cat one can perform following:
1. copy
$cat file1 > file2
2. display
$cat file1
3. create
$cat > file1
4. append
$cat file1 >> file2

with touch command one can create a file of 0 bytes later
you can use it like any other regular files. it is not
replacement for cat. but yet another command.
you cannot perform copy(redirection), display and
concatenation with touch.

which command to use, depends on what is your requirement.
say, you are installing oracle and you have not given proper
permission to oracle users home directory, in that case just
to check it, you can use touch command. here you are
interested in knowing whether you as a oracle user have
permission to write to that directory and not in creating a
file with some contents which you will use in future to do
some manipulation.

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