Paste contents of a file to another file from a particular line - c++

Question

I want to copy content of a text file (description.txt) and paste it on another text file at a particular line (movie.txt) using c++.
Here's the file contents:
description.txt
Chris Gardner takes up an unpaid internship in a brokerage firm after he loses his life's earnings selling a product he invested in. His wife leaves him and he is left with the custody of his son.
movie.txt
Movie name: The Pursuit of Happyness
Movie Description:
// description.txt content here
Initial release: November 2006
Director: Gabriele Muccino
Adapted from: The Pursuit of Happyness

Answer 1

I make a function that you can use.
void CopyContentOfTextFile(char* sourceFile, char* targetFile, int targetLine)
{
FILE* resultFilePtr = fopen("result.txt", "w");
FILE* sourceFilePtr = fopen(sourceFile, "r");
FILE* targetFilePtr = fopen(targetFile, "r");
char line[256];
int lineCounter= 0;
while (fgets(line, 256, targetFilePtr)!=NULL)
{
if (lineCounter == targetLine-1)
{
char lineToBeAdded[256];
//Now read sourceFile
while (fgets(lineToBeAdded, 256, sourceFilePtr) != NULL)
{
fprintf(resultFilePtr, "%s", lineToBeAdded);
}
fprintf(resultFilePtr, "%s", "\n");
}
fprintf(resultFilePtr, "%s", line);
lineCounter++;
}
fclose(sourceFilePtr);
fclose(targetFilePtr);
fclose(resultFilePtr);
//Remove old movie.txt file with new one
remove(targetFile);
rename("result.txt", targetFile);
}
To call it use something like:
int main()
{
char pathToSourceFile[] = "description.txt";
char pathToTargetFile[] = "movie.txt";
int line = 3;
CopyContentOfTextFile(pathToSourceFile, pathToTargetFile, line);
}