mail() & sendmail behavior

[jeofoyster]

I'm using mail to send to several hundred people at once. My question is what is the behavior of the mail() function pertaining to its interaction with sendmail. If I have one to: address and 200 bcc: addresses, does it interact with sendmail to send 201 emails or does it just send one and sendmail takes care of the duplicate sending?

Will mail() wait for sendmail to send 201 emails before it allows the script to continue on with what it's supposed to do, or does it just send the email and move on and let sendmail act independently?

Thanks!

[yelvington]

mail() passes all the work on to sendmail.

Exactly how sendmail behaves depends on whether you are using Sendmail, Exim, Postfix, or some other MTA ... but generally the sendmail interface returns quickly after queueing the data for delivery by other processes.