C++ exec executed bash scripts stops randomly - c++

Question

I'm executing a bash script via execvp but the script stops execution half-way.
Have a look at my code:
int main()
{
char* params[2];
//First Parameter has to be the executable path
params[0] = (char*) ::malloc(sizeof(char) * 40);
::strcpy(params[0], "/home/test.sh");
//execv needs an null pointer as last argument
params[1] = NULL;
//Execute target executable
::execvp(params[0], params);
//Only if ::exec() returns: output error
std::cout << "Exec Failed!";
exit(1);
}
I used the following bash script for testing:
#!/bin/bash -vx
echo "1" >> /home/out.txt
echo "2" >> /home/out.txt
echo "3" >> /home/out.txt
echo "4" >> /home/out.txt
echo "5" >> /home/out.txt
exit 0
Most times the script doesn't even execute, means no file is being created or nothing is being written into an existing file. Somtimes, however the script executes partially or even complete meaning the textfile contains
1
up to
1
2
3
4
5
But no matter what happens inside the bash script the application always exits with error code 0.
Why is this happening?
If i execute the bash script manually everything works fine reaching the end of my script every time. Therefore, i assume it has to do something with my execvp call instead of the bash script.
I'm running, therefore tested the program on an beaglebone black system (am335x) with debian 8.6.

Answer 1

here is what I did to make this program work:
Note: I re-wrote it in C
The proposed C code:
#include <stdio.h> // perror()
#include <stdlib.h> // exit()
#include <string.h> // strcpy()
#include <unistd.h> // execvp()
int main( void )
{
char* params[2];
//First Parameter has to be the executable path
params[0] = "/home/rkwill/rtest.sh";
//execv needs an null pointer as last argument
params[1] = NULL;
//Execute target executable
execvp(params[0], params);
perror( "execvp failed" );
exit(1);
}
then, in my user directory: /home/rkwill/
touch rtest.sh
then edited 'rtest.sh' to contain:
#!/bin/bash -vx
# generate file if not already in existence
touch /home/rkwill/out.txt
echo "1" >> /home/rkwill/out.txt
echo "2" >> /home/rkwill/out.txt
echo "3" >> /home/rkwill/out.txt
echo "4" >> /home/rkwill/out.txt
echo "5" >> /home/rkwill/out.txt
exit 0
Then made the bash script executable via
chmod 777 rtest.sh
Note: I used the directory /home/rkwill because I do not have permission to write in the /home directory.
the first time I ran the program the resulting 'out.txt file contained
1
2
3
4
5
each successive run appended a repeat of the above output to 'out.txt'