initialize a string variable with output of a command?

[Glen]

Hi,

I just have a quick question
Im trying to initialize a string (or char) variable with the information
created by the output of a shell (or DOS) command..

Example:
I want to execute a command such as
system("cat /test.txt | grep something ") or whatever DOS or linux command
and assign the output of that command to the variable str;

so I tried
char str[128]="system(\"my_command\")";

then when I do, cout<<str;
I get system(\"my_command\"),
which is the acctual command, and not its output

Is there any way I can do it?

Thank you

[Kevin Goodsell]

Glen wrote:

Hi,

I just have a quick question
Im trying to initialize a string (or char) variable with the information
created by the output of a shell (or DOS) command..

There is no standard way. Try a group that discusses your particular
platform & C++ implementation.

-Kevin
--
My email address is valid, but changes periodically.
To contact me please use the address from a recent posting.

[Jerry Coffin]

In article <EG*******************@twister.rdc-kc.rr.com>, [e-mail]
says...

Hi,

I just have a quick question
Im trying to initialize a string (or char) variable with the information
created by the output of a shell (or DOS) command..
[ ... ]
Is there any way I can do it?

None is included in the C++ standard, but if you ask about popen in a NG
specific to the OS you're using, there's a pretty fair chance somebody
will be able to help you.

--
Later,
Jerry.

The universe is a figment of its own imagination.

[David Rubin]

Glen wrote:

Hi,

I just have a quick question
Im trying to initialize a string (or char) variable with the information
created by the output of a shell (or DOS) command..

Example:
I want to execute a command such as
system("cat /test.txt | grep something ") or whatever DOS or linux command
and assign the output of that command to the variable str;

so I tried
char str[128]="system(\"my_command\")";

then when I do, cout<<str;
I get system(\"my_command\"),
which is the acctual command, and not its output

Is there any way I can do it?

Try

system("my_command > command.out");
string s;
ifstream ifs("command.out");
std::getline(ifs, s);
ifs.close();

/david

--
Andre, a simple peasant, had only one thing on his mind as he crept
along the East wall: 'Andre, creep... Andre, creep... Andre, creep.'
-- unknown