Based on what you posted sofar:
export $file1=$home1/pip1.$$
mailx -s "This Message from unix"
abc@yahoo.com< $file1
As already pointed the assignment is wrong and should be:
export file1=$home1/pip1.$$
But even then, the question is whether that file actually exists.
$$ is replaced by the proces id of either the process id of the shell you are using if you execute this on the command line, or the process id of the script in which these line occur.
The change a file like that exists is really small unless you created it first.
If we are dealing with a script it might be wise to post the full script.
When you use these lines, either on the command line or within a script, are there any error messages displayed?
If so post them here.
If you use a script for which stderr is redirected, remove this redirection to see the errors.
If the file does exist and the commands do not generate an error message you can try the following command:
mailx -v -s "This Message from unix"
abc@yahoo.com< $file1
This to see if mail is properly configured.
