Q1>How do i read and write to file in shell script. Here is what i want let's assume the filename as "file1"

Read file1

Check the content of file1 which can be either "0" or "1"

if(content == 0)
{
execute a command
}

flush file1(remove all contents in it)

write "1" in to file1

execute a few commands

flush file1(remove all contents in it)

write "0" in to the file

Q2>How do i store the result of a shell script command in a variable.For example

"dropdb something" - When i execute this command on bash it gives a message
"database dropped" how do i capture this in shell and store it in a variable and compare it

Thanks for helping me!