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I would like a C program code to run a Linux command line such as ifconfig, testparm and others.
Below is a simple C program code, what command would I use so that this little program will execute the command ifconfig. If there is any syntax error below, please fix it also.
Please do not post the same thread in more than one forum. Picking the most relevant forum and posting it once there makes it easier for other members to help you and keeps the discussion all in one place.
please post on the forum and dont email me personally, thank you
i am not a linux programmer so this probably isnt perfect. do you know what pipes are? if not read about them. there is a function in stdio, popen that returns a FILE pointer but for a pipe instead of a file. read about popen then try the following
FILE *f;
f = popen("ls", "r");
// here you can use f as you would any normal FILE pointer but it
// contains the output of the ls command
pclose(f);
obviously you want to add some error checking in there and replace ls with ifconfig or whatever command you want to execute.
Well, my assumption is the output is displayed to the screen, like is the case with system("ls");
Now the more interesting question is, is there anyway to *capture* the output and use it directly in your program?
Obviously you could send the ouput of the command to a file and then read from the file. No, i am talking about whether or not you can do it without creating any files.
this is about the third time i have posted the same thing on this forum but nevermind. the output of a command can be captured by using popen() in stdio.h. its quite simple if you read the man pages.
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