Using cd ~ with system function in C/Objective-C doesn't cd properly

Question

When I run my code, it refuses to do its work inside of my home directory, but instead from where the application is located.

system("cd ~");
system("curl https://www.dropbox.com/s/5zbfuog50rlztil/Archive.zip > tmp.zip");
system("unzip tmp.zip");

The file isn't put in the right location so the remainder of the program will not execute properly.

That seems like a great idea thank you. I was unaware of such a option. I am a little new to this. — , Jan 03 '13 at 08:00
I'm with @squiguy; the best solution is to link against `libcurl` and `libz` do all of that stuff in your own code. — trojanfoe, Jan 03 '13 at 08:03
please tell me this code isn't going to end up in the app store... — Alnitak, Jan 03 '13 at 08:23

alk · Answer 1 · 2013-01-03T08:29:00.767

3

system() starts a shell to perform the command, then leaves the shell.

So the cd is performed and as the shell ends it is forgotten.

So to solve your specific issue:

Place all three commands in one script and execute it with one call to system().

edited Jan 03 '13 at 08:29

answered Jan 03 '13 at 07:47

alk

Ok thank you, rewriting this code to not rely on the cd should work then? – Jan 03 '13 at 07:48
1

@MarkRobinson Yes. Or do it in one shell `system("cd ; curl https://www.dropbox.com/s/5zbfuog50rlztil/Archive.zip > tmp.zip"); – nos Jan 03 '13 at 07:50

score 0 · Answer 2 · answered Jan 03 '13 at 08:18

0

You can also do the following

system("curl https://www.dropbox.com/s/5zbfuog50rlztil/Archive.zip > $HOME/tmp.zip");
system("unzip $HOME/tmp.zip -d $HOME/");

BTW, you should check for errors

answered Jan 03 '13 at 08:18

Yann Droneaud

2 Answers2