[C]Renaming/moving a directory - Tilted Forum Project - TFP - Sexuality, Philosophy and Political Discussion

Fallon · 03-01-2004, 08:06 PM

As the subject says, I'm trying to rename/move/delete a directory, but the folder also has stuff in it. I'd prefer to move the directory from ~/mech/player/ to ~/mech/backup if that helps. I tried using a rename function, but that didn't accomplish much. Any help would be greatly appriciated.

Pragma · 03-01-2004, 10:20 PM

Quote:

execve( "mv ~/mech/player ~/mech/backup" );

That could work, assuming you aren't trying to use any variables or whatever to determine where to move, etc.

Fallon · 03-02-2004, 04:45 AM

nope there are variables...
I'll try that though. Thanks a bunch.

Fallon · 03-02-2004, 07:06 AM

that didn't work...
I looked around and couldn't find anything besides something about using system() but I couldn't find anything for that.

kel · 03-02-2004, 08:39 AM

Hrm... Something in between quotes is stored as what in C? A character array?

Generate the array yourself and pass it in as a parameter to execve with the proper variable placement.

Fallon · 03-02-2004, 08:58 AM

I did, I did

PHP Code:


			
sprintf( buf, "mv ../players/%s/ ../backup/%s", name, name");

execve( buf);

And I know it's not php, but makes it more readable...
And that didn't work.

kel · 03-02-2004, 09:04 AM

Anywhoo,
File system operations are the realm of the OS so you won't find them in the standard libraries. You will have to include headers for whichever OS you plan on compiling it under, can I assume something POSIX compliant?

bogosj13 · 03-02-2004, 05:33 PM

Not quite sure why you want to do this with C, a shell script would probably be easier. That being said:

PHP Code:


			
#include <process.h>



int execvp(const char * file, char * const argv[]);

execvp requires two parameters, one being the name of the process image (in this case 'mv'), and an array of strings for the arguments.

Note that execvp replaces the current process with the image of 'mv'. If you want your program to continue running after you exec, you will need to fork() prior to the exec().

I just noticed that you were using execve, which has three parameters, the third being the path. execvp just uses the path from your environment.

Fallon · 03-03-2004, 07:08 AM

Well, I need to be able to move the folder within the program. So forking it isn't really that good of an idea I suppose...

bogosj13 · 03-03-2004, 07:34 AM

Quote:

Originally posted by Fallon
Well, I need to be able to move the folder within the program. So forking it isn't really that good of an idea I suppose...

That was my point. If your program goes like this:

prompt user for something
move files
display success message
prompt user for something

and you use any of the exec() family of functions, your program will work like this:

prompt user for something
move files
terminate

That is because the current process image of YOUR program is overwritten by the 'mv' process image. You need to fork to create an exact duplicate copy of your process, and immediatly replace one of them with the mv exec:

PHP Code:


			
if(fork()){

execvp(...);

}

continue program here

03-01-2004, 08:06 PM	#1 (permalink)
Fallon Junkie Join Date: Apr 2003 Location: RI	[C]Renaming/moving a directory As the subject says, I'm trying to rename/move/delete a directory, but the folder also has stuff in it. I'd prefer to move the directory from ~/mech/player/ to ~/mech/backup if that helps. I tried using a rename function, but that didn't accomplish much. Any help would be greatly appriciated.

03-02-2004, 08:39 AM	#5 (permalink)
kel WARNING: FLAMMABLE Join Date: Apr 2003 Location: Ask Acetylene	Hrm... Something in between quotes is stored as what in C? A character array? Generate the array yourself and pass it in as a parameter to execve with the proper variable placement. __________________ "It better be funny"

03-02-2004, 08:58 AM	#6 (permalink)
Fallon Junkie Join Date: Apr 2003 Location: RI	I did, I did PHP Code: `sprintf( buf, "mv ../players/%s/ ../backup/%s", name, name"); execve( buf);` And I know it's not php, but makes it more readable... And that didn't work.

03-02-2004, 09:04 AM	#7 (permalink)
kel WARNING: FLAMMABLE Join Date: Apr 2003 Location: Ask Acetylene	Anywhoo, File system operations are the realm of the OS so you won't find them in the standard libraries. You will have to include headers for whichever OS you plan on compiling it under, can I assume something POSIX compliant? __________________ "It better be funny" Last edited by kel; 03-02-2004 at 09:11 AM.

03-02-2004, 05:33 PM	#8 (permalink)
bogosj13 Rookie Join Date: May 2003	Not quite sure why you want to do this with C, a shell script would probably be easier. That being said: PHP Code: `#include <process.h> int execvp(const char * file, char * const argv[]);` execvp requires two parameters, one being the name of the process image (in this case 'mv'), and an array of strings for the arguments. Note that execvp replaces the current process with the image of 'mv'. If you want your program to continue running after you exec, you will need to fork() prior to the exec(). I just noticed that you were using execve, which has three parameters, the third being the path. execvp just uses the path from your environment.

03-02-2004, 04:45 AM	#3 (permalink)
Fallon Junkie Join Date: Apr 2003 Location: RI	nope there are variables... I'll try that though. Thanks a bunch.

03-02-2004, 07:06 AM	#4 (permalink)
Fallon Junkie Join Date: Apr 2003 Location: RI	that didn't work... I looked around and couldn't find anything besides something about using system() but I couldn't find anything for that.

03-03-2004, 07:08 AM	#9 (permalink)
Fallon Junkie Join Date: Apr 2003 Location: RI	Well, I need to be able to move the folder within the program. So forking it isn't really that good of an idea I suppose...