Thread: 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);
}

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;

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.