Very Computer

I'm wodering how to send email without system(). Can't figure out the way
passing
 char *msgbody to /bin/mail in execv() in a linux box. any way to do it or
have to use other command. My boss thinks system() is no good, btw.

TIA

sam

It's beyond me way your boss would assume that sytem() is "no good",
but if he pays you to reinvent the wheel... But what do you want to
pass a char pointer to an exec'ed program for? It's going to point
to nothing reasonable in the newly created process anyway. You would
probably better off doing something like this:

1. Create a pipe using pipe(2)
2. Install a handler to catch SIGCHLD signals to avoid a zombie
3. fork(2)

In the child now do:

4C: close(2) write of pipe
5C: call dup2(2) with the read end of the pipe and STDIN as the
    arguments,
6C: call execcv() to replace the childs code by the one of /bin/mail
    with the appropriate command line arguments, i.e.

    const char *my_args[ 5 ];

        my_args[ 0 ] = "/bin/mail";
        my_args[ 1 ] = "-s"
    my_args[ 2 ] = "The subject line"

    my_args[ 4 ] = NULL;

    execv( my_args[ 0 ], my_args );

In the parent you do

4P: close(2) the read end of pipe
5P: copy the message using write(2) to the write end of the pipe
6P: close(2) the write end of the pipe

That's basically everything you need. Things would be even simpler
if you are allowed to use popen(3) and pclose(3), then all you
need to call popen() with the mail-command, then write to the
newly created stream and finally close it.

                                Regards, Jens
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  \___/ens|_|homs|_|oerring

Quote:> I'm wodering how to send email without system(). Can't figure out the way
> passing
>  char *msgbody to /bin/mail in execv() in a linux box. any way to do it or
> have to use other command. My boss thinks system() is no good, btw.

    Get a copy of any good book on UNIX programming. Read the section on
using pipes in conjunction with fork/exec. You can probably get away with
using 'popen'.

    Comments like "system() is no good" are meaningless. Without citing a
specific problem or type of problem, he could mean that 'system()' is no
good for frying eggs.

    DS

He might be concerned about potential security problems.  system()
invokes the shell.

RFM
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To reply, translate domain from l33+ 2p33|< to alpha.
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On Tue, 8 Jul 2003 15:33:48 +0000 (UTC),

So he should have explained that.  Most of us have lost the ability to
mind read long time ago.

Villy