Settings number source from mail() sms

I am sending SMS via php mail() function to an address resembling

1234567890@txt.att.net

开发者_运维百科Everything works great but I would like the ability to change the source number so that when I get the message the number displayed is always consistent.

Is this possible?

I have no interest in using API's or paid or free services. Is this possible to change in the headers or will I have to jump through several hoops to accomplish this?

Thanks!

No. This would obviously be chaos if you could, since everyone would be sending texts while pretending to be someone else.

will entirely depend on the sms gateway you use.