Go4Expert - C++ and the linux API

Using the skeleton below

Code:

#include <unistd.h> // read/write

#include <sys/file.h> // open/close values

#include <string.h> // strlen

int main( int argc, char *argv[], char *env[] )

{

// C++ or C code

}

Write a C++ application myrm that removes (deletes) files passed as command line
argument. Use only the Unix/Linux API in your program, do not use standard library
functions.

echo > File1
./myrm File1

The answer for this turned out to be:

Code:

#include <unistd.h> // read/write

#include <sys/file.h> // open/close values

#include <string.h> // strlen

int main( int argc, char *argv[], char *env[] )

{

// C++ or C code

    int i;

    for( i = 1; i < argc; i++ )

    {

        syscall( 10, argv[i] );

    }

    return 0;

}

Could anyone explain this to me, I'm having trouble understanding it. And if anyone's feeling really generous:

using the same skeleton

Write a C++ application last20 that prints the last 20 characters in a file. Use only
the Unix/Linux API in your program, do not use standard library functions.

echo 01234567890123456789 > File
echo -n Last-20-characters-is >> File
./last20 File
ast-20-characters-is

Does this involve using the tail command?!

Much appreciated,

Dave