Thread: Convert list of names from one text file to email format in a new file

Hello everyone,

I'm a total self-taught (so far) newbie here, so please bear with me. I have almost a hundred names in a text file that I want to convert to email addresses and save to another file. I seem to have it working, but it doesn't print the full names in the email prefix. The output I'm looking for is Doe_John@livebrandm, but I'm only getting D_J@livebrandm. I'm not sure what I should specifically be reading up on that applies to this directly. I would appreciate any help with this.

Code:

#include <stdio.h>
#include <stdlib.h>


int main(void)
{
    
    FILE *fpin=fopen("namesIN.txt", "r"); 
    FILE *fpout=fopen("emailOUT.txt", "a");
    char first[20],last[20],inbuff[1500];
    
    if((fpin=fopen("namesIN.txt","r"))==NULL)
    {
        printf("\nCannot open input file");
        exit(1);
    }
    if((fpout=fopen("emailOUT.txt","a"))==NULL)
    {
        printf("\nCannot open output file.txt");
        exit(2);                
    }                    


    while(fgets(inbuff,1500,fpin) !=NULL)
    {
        sscanf(inbuff,"%S%S",first,last);
        printf("%s_%[email protected]\n",last,first);
        fprintf(fpout,"%s_%[email protected]\n",last,first);
    }
    
    fclose(fpin);
    fclose(fpout);
    return 0;
    }

namesIN.txt

Try changing your sscanf() specifiers to "%s", "%S" is not a valid standard C specifier.

Jim

Aha! Finally I have Colonel Sanders' email address!

@oogabooga Thanks a lot for the quick reply. It was right under my nose and I just couldn't see it. I guess that'll get easier as I get better at this. Thanks for the file opening heads up too. You guys are awesome!

Originally Posted by oogabooga

Apparently a capital S is an extension (in gcc at least) that is equivalent to the standard %ls, which expects a wchar_t pointer.


This will actually read the entire name, but store it (on my machine at least) as the ascii value of the first letter followed by a zero byte, then the ascii value of the second letter followed by a zero byte, etc., and finally two zero bytes (a wchar_t null character). So when you print it with a %s specifier, the first zero byte is interpretted as the end sentinel. Hence you end up with just the first letter.


Turning up the warning level on your compiler may warn you of the mismatch between the specifier and the proferred pointer. gcc gives such a warning with the -Wall flag.

I'll be saving this post so that when I become a real coder I can read it && understand it. lol

Hey again, folks. I tried to make what I thought would be a simple tweak to the output in this program, but I'm having a little problem. Instead of printing the full first name in the prefix of the emails, I wanted to change it to just the first initial. Basically I want to change the output from doe_John@livebrandm to doe_j@livebrandm. I changed the second %s to %c in printf and fprintf on lines 27 and 28:

Code:

printf("%s_%[email protected]\n",last,first);
fprintf(fpout,"%s_%[email protected]\n",last,first);

and now the output just reads: doe_@@livebrandm, giving me a second @ symbol rather than a first initial. The %c and adding a "system("pause") at the end were the only changes I made. Can someone point out where I'm screwing up at please?

first isn't a character, so can't be printed using %c. If you wanted a particular char out of that char array, well, that's why there's [array notation].

Originally Posted by tabstop

first isn't a character, so can't be printed using %c. If you wanted a particular char out of that char array, well, that's why there's [array notation].

Thank a lot. I hadn't known about array and pointer notation yet. I looked them up real quick and got things working again with the newly desired output. Thanks again!