Removing a Line from a File without making a new file - c++

Question

I'm trying to remove a single line from a file without creating a new file. For example in the file before it is modified it would be:
This
is
a
file
and after it would be:
This
a
file
However, with the way I'm currently trying to do it what happens is
This
a
file
I know I could do it by writing only the contents that I want into another file and then renaming that file and deleting the old one but I wanted to know if there is another way besides that.
I've tried using
if (string::npos != line.find(SPSID))
{
iPos = (pos - line.size() - 2);
stream.seekg(iPos);
for (int i = (pos - line.size() - 2); i < pos; i++)
{
//Sets input position to the beginning of the current line and replaces it with NULL
stream.put(0);
}
stream.seekp(iPos);
pos = stream.tellp();
}
as well as replacing stream.put(0); with stream.write(nullLine, iPos);
but neither have worked.
int Delete(string fileName, string SPSID)
{
//Variables
string line;
char input[MAX_CHAR];
fstream stream;
streamoff pos = 0;
streamoff iPos = 0;
//Opening and confirming opened
stream.open(fileName);
if (!stream.is_open())
{
cout << "File Did not open.\n" << endl;
return -1;
}
//Loops until the end of the file
do
{
//Gets one line from the file and converts it to c++ string
stream.getline(input, MAX_CHAR, '\n');
line.assign(input);
//Finds the current output position (which is the start of the next line)
pos = stream.tellp();
//Finds and checks if the SPSID is in the string. If it is then print to screen otherwise do nothing
if (string::npos != line.find(SPSID))
{
iPos = (pos - line.size() - 2);
stream.seekg(iPos);
for (int i = (pos - line.size() - 2); i < pos; i++)
{
//Sets input position to the begining of the current line and replaces it with ""
stream.put(0);
}
stream.seekp(iPos);
pos = stream.tellp();
}
} while (stream.eof() == false); //Checks that the end of the file has not been reached
stream << "Test" << endl;
//Resets the input and output positions to the begining of the stream
stream.seekg(0, stream.beg);
stream.seekp(0, stream.beg);
//Closing and Confirming closed
stream.close();
if (stream.is_open())
{
cout << "File did not close.\n" << endl;
return -2;
}
return 0;
}
I'm probably gonna have to make a new file and rename it but figured it was still worth asking if this is possible. :/