topic Re: Using system Function call in HP UNIX in Operating System - Linux

Using system Function call in HP UNIX

CA1490051 — Thu, 21 Feb 2008 14:07:08 GMT

Hi All,

I want to rename a file in a C++ Program.
So i am using the system function call as follows .

int amin()
{
string src="Test.txt";
string Dest = "Test_1.txt"
system("mv Src Dest");
}
But if i execute the program the error message saying Src no such file or directory is displayed.

I also tried to do this by calling a shell script in the system function call as follows
int amin()
{
string src="Test.txt";
string Dest = "Test_1.txt"
system("./Move.sh Src Dest");
}

Move.sh is as follows
mv $1 $2

But, again the same error.

Can some one help me to achive this.

thanks in advance
Vikram

Re: Using system Function call in HP UNIX

Torsten. — Thu, 21 Feb 2008 14:15:52 GMT

Your system is trying to do exactly what you wrote:

system("mv Src Dest");

# mv Src Dest

Do you have a file called "Src"?
No? Precisely.

Re: Using system Function call in HP UNIX

James R. Ferguson — Thu, 21 Feb 2008 14:29:33 GMT

Hi:

Does your environment's PATH reflect where your files reside?

For that matter, why write a C or C++ program only to call 'system()' to rename a file? You should call 'rename()' [assuming that the source and destination reside within the same filesystem].

Regards!

...JRF...

Re: Using system Function call in HP UNIX

Hein van den Heuvel — Thu, 21 Feb 2008 14:33:18 GMT

Dear Vikram,

STOP!

Take your fingers from the keyboard and slowly turn around.
Walk to the nearest bookshelf and pick up a basic programmign book.
Any language.
even K&R C would be a good start.
Focus on VARIABLES.
Spend a few quality hours with the books. Now turn back.

But don't touch that compiler just yet.
Look around some first, notably with the 'man' pages.

Specifically type, and read,
man rename
man sprintf

Welcome to the wonderous world of programming!

Regards,
Hein.

Re: Using system Function call in HP UNIX

Torsten. — Thu, 21 Feb 2008 14:37:34 GMT

...
if ( rename(Src, Dest) == 0 )
printf("%s renamed to %s\n", Src, Dest);
else
perror("rename");

return 0;
...

Re: Using system Function call in HP UNIX

CA1490051 — Thu, 21 Feb 2008 14:57:04 GMT

Hi All,

I can rename the file using rename(). But, now i want it to tar and zip it.

Can any one tell me how to achive this?

system("tar -cvf file.tar file");

Obviously the shell will complain that file not found.
Where file for me is a string variable
initialised to "Temp.txt";

thaks and regards
Vikram

Re: Using system Function call in HP UNIX

Torsten. — Thu, 21 Feb 2008 15:04:15 GMT

As mentioned above (directly and indirectly) - learn to work with variables!

From your initial question:

system("mv Src Dest");

Src and Dest are **NAMES** - not variables from the system point of view!

Re: Using system Function call in HP UNIX

CA1490051 — Thu, 21 Feb 2008 15:08:21 GMT

Hi All,

Yes i know these are variables. But, still there is a requirement that i should achive this.

Any way to do this will be great help for us.....

thanks and regards
Vikram

Re: Using system Function call in HP UNIX

Torsten. — Thu, 21 Feb 2008 15:13:06 GMT

"Yes i know these are variables"

Really? But you don't handle them as variables.

man system:

SYNOPSIS
#include

int system(const char *command);
...

You need to *build* the command string first!

Re: Using system Function call in HP UNIX

James R. Ferguson — Thu, 21 Feb 2008 15:27:00 GMT

Hi (again) Vikram:

> Yes i know these are variables. But, still there is a requirement that i should achive this.

This seems like a purely academic exercise. I agree with both Hein and Torsten's comments which are meant to be helpful. The use of 'system()' to perform shell tasks in a C program says that you may need to rethink your objective and your use of tools.

Regards!

...JRF...

Re: Using system Function call in HP UNIX

Laurent Menase — Thu, 21 Feb 2008 16:43:14 GMT

int main()
{
char *src="Test.txt";
char * Dest = "Test_1.txt"
char commande[256];

sprintf(commande,"/usr/bin/mv %s %s",Src,Dest);
system(commande);
}

Re: Using system Function call in HP UNIX

CA1490051 — Fri, 14 Mar 2008 07:03:54 GMT

Hi Laurent,

Thank you very much for the solution

regards
Vikram