File I/0

So, I have posted here before and you have all been a great help. My problem is that I am still a really bad programmer. :)

I am attempting to read in data from a text file and have a couple of questions.

1) How do I read in data, but exclude the quotation marks and commas?
2) How do I add an eof statement to stop my endless while loop.

THANKS!!

Sample of my text file:

Code:

---

"#2",,0,130.00,170.00
"#2ACSR",,0,160.00,230.00
"#2AL",,0,168.00,230.00
"#2CU",,0,216.00,294.00

---

Here is my code:

Code:

---

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

#define MAX_NUMBER_CONDUCTORS        26
#define COND_DATA_LENGTH                5
#define COND_FILENAME                        "tblConductor.txt"
#define LOG_FILENAME                        "DCA.log"

static FILE *log_file;
static FILE *cond_file;

int main(void)
{
        char cond_name[ MAX_NUMBER_CONDUCTORS ][ COND_DATA_LENGTH ];
        int ud_flag[ MAX_NUMBER_CONDUCTORS ];
        float summer_amp[ MAX_NUMBER_CONDUCTORS ];
        float winter_amp[ MAX_NUMBER_CONDUCTORS ];

        struct tm *newtime;
        time_t aclock;

        // open logging file

        if ((log_file = fopen( LOG_FILENAME, "a+" )) == NULL)
                fprintf(stderr, "\nERROR - Cannot open <%s>\n", LOG_FILENAME);
        else {
                // write start-up message
                time( &aclock );
                newtime = localtime( &aclock );
                fprintf(log_file, "\nDCA v1.0 BEGINNING %s\n",asctime(newtime));
                fprintf(stderr, "\nDCA v1.0 BEGINNING %s\n", asctime(newtime));
                // close logging file
                fclose (log_file);
        }

        // open conductor file

        cond_file = fopen( COND_FILENAME, "r" );
        int i = 0;

        while ( cond_file != NULL ) {
                fscanf( cond_file, "%s,,%d,%f,%f", cond_name[i], &ud_flag[i], &summer_amp[i],
                                &winter_amp[i] );
                        if ((log_file = fopen( LOG_FILENAME, "a+" )) == NULL)
                                fprintf(stderr, "\nERROR - Cannot open <%s>\n", LOG_FILENAME);
                        else {
                                // open log file again
                                fprintf(log_file, "Conductor Name: %s  UD Flag: %d  Summer Amp: %f  Winter Amp: %f\n",
                                        cond_name[i], ud_flag[i], summer_amp[i], winter_amp[i]);
                                // close logging file
                                fclose (log_file);
                        }
                printf( "Conductor Name: %s  UD Flag: %d  Summer Amp: %f  Winter Amp: %f\n",
                        cond_name[i], ud_flag[i], summer_amp[i], winter_amp[i]);
                i++;
        }

        fclose( cond_file );

        return(0);
}

---

If your input looks like:

"#2",,0,130.00,170.00

then you can use scanf to read and parse your lines of code:

Example:

Code:

---

/* Note: this is a sample of using scanf, this won't directly help your code as is. */

#define BUF_SIZE 256
void readFile(const char *filename) {
  FILE *file;
  char buffer[BUF_SIZE], *quoted, *ptr;
  float a, b, c, d;

  if((file = fopen(filename, "r"))) {
    while(fgets(buffer, BUF_SIZE, file)) {
      if((ptr = strrchr('\"', buffer))) {
        ptr+=2;  // skip '",'
        quoted = buffer+1; // skip '"'
        sscanf(ptr, "%g,%g,%g,%g", &a, &b, &c, &d);
     
      // make use of your info now.
    }

    fclose(file);
  }
}

---

The above doesn't guarantee the input is correct but you can figure that part out.

What I usually do is parse the entire file or portion of the file I need to work with specifically and store it into a char array. Then I iterate through the array looking for specifics entries to remove.

This is a function I wrote for a script parser I had to write. You probably won'tbe able to copy and paste it, but maybe it'll spark some ideas for you.

Notes: String is typedefined as a char*, it is not a class. This was written in C, but removes only C++ style comments at current. Using the implementations, it is only an extra step to remove C style /* */ as well.

Code:

---

//////////////////////////////////////////////////////////////////////////
// Removes comments from string buffer holding the file
//
// Parameters
// strBuffer        ->        String to remove comments from.
//////////////////////////////////////////////////////////////////////////

void RemoveComments(String strBuffer)
{
        int iTest, iLoc;
       
        for(iTest = iLoc = 0; iTest < iCharCount; ++iTest)
        {
                if(strBuffer[iTest] == '/' && strBuffer[iTest+1] == '/')
                {
                        while(strBuffer[iTest+1] != '\n')
                                ++iTest;
                }
                else
                {
                        strBuffer[iLoc] = strBuffer[iTest];
                        ++iLoc;
                }
        }
        strBuffer[iLoc] = '\0';
        iCharCount = iLoc;
}

---

Thanks for the replies, but I guess that wasn't exactly what I was looking for. Let me try again...

What specific code could be used to ignore commas and parentheses?

Also, what code could be used to read in each data as a separate variable?

I am looking to tweak my existing code and not totally re-write it. I think I'm on the right track, but just need a bit of guidance.

Thanks again!

What you just asked seems to undo what you asked above.

Do you want the comma as a field separator?
Do you want the parens - ( ) as field separators?

You can throw away a field separator, too.

My code does what you want. I just noticed that I should have a line that looks like this:

Code:

---

*ptr = 0;

---

before the line that looks like this:

Code:

---

ptr += 2;

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But other than that little mistake my code will do exactly as you wanted. Obviously it was an example of the theory, but I think thats all you need to get started.