Shell command in .m file?

Question

I tried using system() to run a shell command in a .m file, but to no avail. How is it possible to run a shell command from a .m file in Xcode?

#import "AppController.h"


@implementation AppController
- (void)awakeFromNib
{
    [output setStringValue:@"Awaiting orders, sir."];
}

- (IBAction)convertFile:(id)sender
{
    NSString *string = [input stringValue];
    NSString *string2 = @"tar czvf ProjectFiles.tar.gz ";



    NSString *stringCmd = [NSString stringWithFormat:@"%@ %@", string2, string];

    system(stringCmd);
}
@end

It is. How were you using it? – mipadi May 20 '11 at 15:31 — mipadi, May 20 '11 at 15:31
`system()` works. Please post the relevant code. – Rafe Kettler May 20 '11 at 15:34 — Rafe Kettler, May 20 '11 at 15:34

score 1 · Answer 1 · answered May 20 '11 at 15:57

1

NSTask is an alternative. Check out the NSTask Class Reference

answered May 20 '11 at 15:57

JimDusseau

729
6
6

So - (void)setLaunchPath:(NSString *)path? – Mike May 20 '11 at 16:46
NSTask is a good alternative to system indeed. For usage examples, you can search NSTask on stackoverflow, e.g. http://stackoverflow.com/questions/5211737/nstask-question – diciu May 20 '11 at 19:28

score 0 · Answer 2 · answered May 20 '11 at 19:22

0

Your code failed because system expects a C string (char *) and your stringCmd is a NSString *.

Try using:

system([stringCmd cStringUsingEncoding:NSASCIIStringEncoding]);

Also note that system runs the command in a shell so be aware for potential security problems. If your input string is @"tt.txt; echo \"aa\"" your code will run

tar czvf ProjectFiles.tar.gz tt.txt; echo "aa"

This may or not be what you intend.

answered May 20 '11 at 19:22

diciu

29,133
4
51
68

echo "aa" is just an example. It could just as well be "rm -rf /" or some other destructive command. – diciu May 21 '11 at 20:06

Shell command in .m file?

2 Answers2