C++: Why am I getting an error: "array initializer must be an initializer list or string literal" when I am in fact using a string?

Question

So here is my question. I am tring to run a program I found online and it is failing to compile. Why am I getting an error: "array initializer must be an initializer list or string literal" when I am in fact using a string? I know this code works for others running windows, but not for me on the m1 Mac.

I am trying to initialize a string array using

string f[3] = " ";

#include <iostream>
#include <cstdio>
#include <string.h>
#include <unistd.h>
#include <cstdlib>

using namespace std;

int main()
{
    bool cont = true;
        
    char buffer[100] = {};

    while (cont)
    {
        cout << "\n\nEnter a command: ";
        
        cin.get (buffer, 90);
    
        //REMOVE
        if (strstr (buffer,"remove") != NULL)
        {
            char* t = strchr (buffer,' ');

            if(t != NULL)
            {
                if(remove( t+1 ) != 0)
                    cout << "\n\nError deleting the file.";
                else
                    cout << "\n\nThe file has successfully been deleted.";
            }
    
            else
                cout << "\n\nInvalid command. Filename not entered.";

        }

        //EXIT
        else if (strstr (buffer,"exit") != NULL)
            cont = false;
        

        //RENAME
        else if (strstr (buffer,"rename") != NULL)
        {
            char* t = strchr (buffer,' ');
            
            if (t != NULL)
            {
                char* oldName = t + 1;  
                    char* newName = strchr (oldName, ' ');


                if (newName != NULL)
                {
                    char temp[30] = {};
                    
                    int i = 0;
                    for(char* start = oldName; start != newName; start++)
                    {
                        temp[i] = *start;
                        i++;
                    }

                    newName++;
                

                    if(rename( temp , newName ) != 0)
                        cout << "\nError renaming the file.";
                        else
                        cout << "\nThe file has successfully been renamed.";
                }   
                    
                else
                    cout << "\n\nNew Name of the file not entered.";
            }
            
            else
                cout << "\n\nInvalid command.";

        }


        //RMDIR
        else if (strstr (buffer,"rmdir") != NULL)
        {
            char* t = strchr (buffer,' ');

            if(t != NULL)
            {
                if(rmdir( t+1 ) != 0)
                    cout << "\n\nError deleting the directory.";
                else
                    cout << "\n\nThe directory has successfully been removed.";
            }
    
            else
                cout << "\n\nInvalid command. DirectoryName not entered.";

        }
        

        //ECHO
        else if (strstr (buffer,"echo") != NULL)
        {
            char* t = strchr (buffer,'"');

            if (t != NULL)
            {
                char* data = t + 1; 

                //Extracting the data
                char temp[200] = {};
                
                int i = 0;

                for(; data[i] != '"'; i++)
                {
                    temp[i] = data[i];
                }


                //Checking if filename is given or not
                    char* fileN = strchr (data + i, ' ') ;

                if (fileN != NULL)
                {
                    fileN++;
                
                    // create a FILE typed pointer
                    FILE *file_pointer; 
    
                    // open the file for writing
                    file_pointer = fopen (fileN, "w");
                    
                    if (file_pointer != NULL)
                    {
                        // Write to the file
                        fprintf (file_pointer,"%s", temp);
    
                        // Close the file
                        fclose (file_pointer); 
                    
                        cout << "\n\nThe file has been successfully created.";
                    }
                    
                    else
                        cout << "\n\nCould not create the file.";
                }   
                    
                //If filename isn't given then simply print the data on console
                else
                {
                    cout << endl << endl << temp;
                }
            }
    
            else
                cout << "\n\nInvalid command. Data not given";
        }

        //UNZIP
        else if (strstr (buffer,"unzip") != NULL)
        {
            char* t = strchr (buffer,' ');

            if(t != NULL)
            {
                char temp[50] = "tar xvf";
    
                if( system( strcat(temp,t) ) != 0 )
                    cout << "\n\nError unzipping the file.";
                else
                    cout << "\n\nThe file has been successfully unzipped.";
            }
    
            else
                cout << "\n\nInvalid command. FileName not entered.";   
        }

        
        //ZIP
        else if (strstr (buffer,"zip") != NULL)
        {
            char* t = strchr (buffer,' ');

            if(t != NULL)
            {
                char temp[50] = "tar cvf";

                if( system( strcat( temp,t) ) != 0 )
                    cout << "\n\nError zipping the file.";
                else
                    cout << "\n\nThe file has been successfully zipped.";
            }
    
            else
                cout << "\n\nInvalid command."; 
        }

        
        else if (strstr (buffer,"out") != NULL)
        {
            int i = 1;
    
            //Checking '-l'
            bool lineByLine = false;
            char* lpos = strstr (buffer,"-l");              
            
            if (lpos != NULL)
            {   
                lineByLine = true;
                i++;
            }
    
            string s(buffer);
            string fileN = "";              
                    
            string delimiter = " "; 
            size_t pos = 0;
        
            while ( i > 0 )
            {   
                pos = s.find(delimiter);
                s.erase(0, pos + delimiter.length());
                i--;
            }
            

            //Now extracting the file names
            string f[3] = " ";
            
            i = 0;

            while ( (pos = s.find(delimiter)) != -1)
            {
                f[i] = s.substr(0, pos);
                    s.erase(0, pos + delimiter.length());
                i++;
            }

            //if atleast one filename is present
                
            if ( s != "out" && s != "-l" && s != "" )
            {
                f[i] = s;
        
                //Opening the files and printing the contents
    
                int c;
                FILE *file;
                
                int j = 0;
    
                bool delay = false;
                char x;         

                while ( j <= i)
                {               
                    char fName[50];
                    strcpy(fName, f[j].c_str());

                    //Printing the contents of the file(s)

                    file = fopen(fName, "r");
                    char line[256];
                    
                    cout << "\n\nThe contents of the file " << fName << " are as follows : \n\n";

                    if (file)
                    {
                        if (lineByLine)
                        {   
                            while (fgets(line, sizeof(line), file)) 
                            {
                                        printf("%s", line);
                                
                                //Delay loop
                                delay = true;
                
                                while(delay)
                                {   
                                    cout << "\n\nPress some key to print the next line\n\n";
                                    getchar();
                                    delay = false;  
                                }                        
                                }

                        }
                
                        else
                        {
                                while ((c = getc(file)) != EOF)
                                putchar(c);
                        }

                        
                            fclose(file);
                    }
    
                    else
                        cout << "\n\nCould not open the file " << fName << " .";
    
                    j++;
    
                    //Delay loop
                    delay = true;
                
                    while(delay)
                    {   
                        cout << "\n\nPress some key to continue\n\n";
                        getchar();
                        delay = false;  
                    }
                }
            }
            
            else
                cout << "\n\nNo filename entered.\n\n";         
        }

        else
            cout << "\n\nInvalid Command. Kindly enter a valid command.";


        cin.ignore();
    }



    cout << "\n\n\nExiting the CLI.\n\n";
    
    return 0;
}

Answer 1

If you are trying to create a string of length 3, you should do this:

string f(3, ' ');

If you are trying to create an array of 3 different strings, then the issue with your code is that you have a type mismatch - you are trying to assign a single string to an array of strings. Instead, you would want to do this:

string f[3] = {" ", " ", " "};

Looking at your code, it looks like you want to create an array of strings. However, it also looks like you could be reading in any number of strings (unless there is some logic in your code where you are confident it will always be 3?) so I recommend using a std::vector .

 std::vector<std::string> f;

Which you can add strings to with the push_back() method like this:

f.push_back(s.substr(0, pos));