how do I store stdout value from system(); into a char* variable? 1

[everyoneca]

how do I store stdout value from system(); into a char* variable?

e.g.

I have child process that executes system(); function, but the output is displayed on server binary tty,

I would like to store the output of system("ls -la");

into a char* variable for later use / display .



is this possible ?

thanks,

taylor

 

[TrojanWarBlade]

Try "popen" instead of "system". It allows you to execute a process and have it's output appear as a file that you can read.



Trojan.

 

[everyoneca]

can you provide a short code example of popen(); storing the stdout value of "ls -la" or "netstat" into a char* type or string variable?

thankyou for your help

 

[everyoneca]

I may have found an example:

#include <stdio.h>

main()
{
FILE *fp;
char line[130];/* line of data from unix command*/

fp = popen("ls -l", "r");/* Issue the command.*/

/* Read a line*/
while ( fgets( line, sizeof line, fp))
{
printf("%s", line);
}
pclose(fp);
}

----

 

[ArkM]

It seems the simplest way: use output redirection in cmd string:

system("myprog >myprogstdout.txt");

Now read (and don't forget to delete a file...

 

[TrojanWarBlade]

Why waste disk space and have to worry about not treading on other files when "popen" gives you an open file handle to the stream directly?



Trojan.