Thread: File I/O program

Hi ,

This is my first post in the forum. I am reading some data from the file and printing it in certain format on the screen. I guess reading part is fine but printing is somewhat messed up. Its tv guide program. The data file contains channels and the program timings. Following is my program

Code:

#include <stdio.h>

void getprograminfo(char *, char *, char *);
char * getline(FILE *);

int main(int argc, char *argv[])
{
	FILE *fp;
	int channels;
	char channelname[20];
	char *line;
	char *linep;
	int i,a,len;
	char time[50];
	char program[50];
	char line1[1024];
	char line2[2000];
	int tlen,plen;

	if (argc < 2)
	{
		printf(" USAGE: %s <filename>\n",argv[0]);
		exit(0);
	}


	if ((fp=fopen(argv[1],"r")) == NULL)
	{
		printf("can not open the file\n");
		exit(0);
	}

	fscanf(fp,"%d",&channels);

	printf("Total Channels: %d\n",channels);

	while (!feof(fp))
	{
		memset(channelname,'\0',20);
		
		GETCHANNEL:
		linep=getline(fp);

		if (linep!=NULL)
		{
			if ((line=strstr(linep,"=")) != NULL)
			{
				//printf("linep1: %s\n",linep);
				strcpy(channelname,++line);
				printf("channel: %s\n",channelname);
			}
		} else {
			goto GETCHANNEL;
		}

		//printf("linep2: %s\n",linep);
		//printf("Check 1\n");
		memset(line1,'\0',sizeof(line1));
		memset(line2,'\0',sizeof(line2));
		for (i=0;i<5;i++)
		{
			memset(linep,'\0',sizeof(linep));
			memset(time,'\0',sizeof(time));
			memset(program,'\0',sizeof(program));

			if ((linep=getline(fp)) == NULL)
			{
				continue;
			}

			//printf("linep: %s\n",linep);

			getprograminfo(linep,time,program);
			//printf("time: %s ",time);
			//printf("program: %s\n",program);

			if (i == 0)
			{
				sprintf(line1,"Time\t\t%s",time);
				sprintf(line2,"Program\t\t%s",program);
				//printf("tlen: %d plen: %d\n",strlen(line1),strlen(line2));
			} else {
				strcat(line1,"\t");
				strcat(line1,time);
				strcat(line2,"\t");
				strcat(line2,program);
				//printf("tlen: %d plen: %d\n",strlen(line1),strlen(line2));
			}
		}
		printf("%s\n%s\n",line1,line2);
		if (strlen(line1) > strlen(line2))
		{
			len = strlen(line1);
		} else {
			len = strlen(line2);
		}
		for (a=0;a<len;a++)
		{
			printf("-");
		}
		printf("\n");
			
	}

	fclose(fp);

	return 0;

}

void getprograminfo(char *line, char *time, char *program)
{
	int i,j;
	char tword[50];
	char pword[50];
	
	i=j=0;

	while (i<strlen(line))
	{
		if (line[i] == ' ')
		{
			tword[j]='\0';
			strcpy(time,tword);
			i++;
			strcpy(program,line+i);
			j=0;
			return;
		} else {
			tword[j]=line[i];
			i++;
			j++;
		}
	}
}

char * getline(FILE *fp)
{
	static char line[100];
	char ch;
	int i=0;

	memset(line,'\0',sizeof(line));
	
	while ((ch=fgetc(fp))!='\n')
	{
		line[i]=ch;
		i++;
	}
	line[i+1]='\0';
	//printf("line length: %d\n",strlen(line));

	if (strlen(line) == 1)
	{
		return NULL;
	} else {
		return line;
	}
}

Following is the file i am reading from

8
=ABC
18.00 Dr Who: Underworld
18.30 Collectors
19.00 News
19.30 The 7.30 Report
20.00 Catalyst
=Seven
18.00 Seven News
18.30 Today Tonight
19.00 Home and Away
19.30 My Restaurant Rules
20.30 **END

Following is the program output.

[root@linux-outside snoopy]# ./tvguide tc.txt
Total Channels: 8
channel: ABC
Time 18.00 18.30 19.00 19.30 20.00
Program Catalyst Report Underworld
-------------------------------------------------------------------------
channel: Seven
Time 18.00 18.30 19.00 19.30 20.30
Program **ENDstaurant Rules
------------------------------------------------------------------------------

Any guess, what am i doing wrong?

Thanks,

You're not including <string.h> for your str* functions and memset. Also, refer here for why using !feof(fp) in a loop is wrong.

Okey Thanks, changed it as per the link. Still the same problem. Any help.??

Code:

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

void getprograminfo(char *, char *, char *);
char * getline(FILE *);

int main(int argc, char *argv[])
{
	FILE *fp;
	int channels;
	char channelname[20];
	char *line;
	char linep[100];
	int i,a,len;
	char time[50];
	char program[50];
	char line1[1024];
	char line2[2000];
	char *temp;
	int tlen,plen,first;

	if (argc < 2)
	{
		printf(" USAGE: %s <filename>\n",argv[0]);
		exit(0);
	}


	if ((fp=fopen(argv[1],"r")) == NULL)
	{
		printf("can not open the file\n");
		exit(0);
	}

	fscanf(fp,"%d",&channels);

	printf("Total Channels: %d\n",channels);
	
	i = 0;
	first = 1;
	
	memset(line1,'\0',sizeof(line1));
	memset(line2,'\0',sizeof(line2));

	while ((fgets(linep,sizeof(linep),fp))!=NULL)
	{
		memset(channelname,'\0',20);		
		linep[strlen(linep)-1]= '\0';

		if ((line=strstr(linep,"=")) != NULL)
		{
			if (!first)
			{
				
				printf("%s\n%s\n",line1,line2);
				if (strlen(line1) > strlen(line2))
				{
					len = strlen(line1);
				} else {
					len = strlen(line2);
				}
				for (a=0;a<len;a++)
				{
					printf("-");
				}
				printf("\n");
				memset(line1,'\0',sizeof(line1));
				memset(line2,'\0',sizeof(line2));
				i=0;
				
			} 	
			first = 0;				
			strcpy(channelname,++line);
			printf("channel: %s\n",channelname);
			
		} else {
			memset(time,'\0',sizeof(time));
			memset(program,'\0',sizeof(program));
			getprograminfo(linep,time,program);
			//printf("time: %s ",time);
			//printf("program: %s\n",program);

			if (i == 0)
			{
				sprintf(line1,"Time\t\t%s",time);
				sprintf(line2,"Program\t\t%s",program);
				//printf("tlen: %d plen: %d\n",strlen(line1),strlen(line2));
			} else {
				strcat(line1,"\t ");
				strcat(line1,time);
				strcat(line2,"\t ");
				strcat(line2,program);
				//printf("tlen: %d plen: %d\n",strlen(line1),strlen(line2));
			}
			i++;
		}
	}

	printf("%s\n%s\n",line1,line2);
	if (strlen(line1) > strlen(line2))
	{
		len = strlen(line1);
	} else {
		len = strlen(line2);
	}
	for (a=0;a<len;a++)
	{
		printf("-");
	}
	printf("\n");

	fclose(fp);

	return 0;

}

void getprograminfo(char *line, char *time, char *program)
{
	int i,j;
	char tword[50];
	char pword[50];
	
	i=j=0;

	while (i<strlen(line))
	{
		if (line[i] == ' ')
		{
			tword[j]='\0';
			strcpy(time,tword);
			i++;
			strcpy(program,line+i);
			j=0;
			return;
		} else {
			tword[j]=line[i];
			i++;
			j++;
		}
	}
}

char * getline(FILE *fp)
{
	static char line[100];
	char ch;
	int i=0;

	memset(line,'\0',sizeof(line));
	
	while ((ch=fgetc(fp))!='\n')
	{
		if (ch == EOF)
		{
			return NULL;
		} else {
			line[i]=ch;
			i++;
		}
	}
	line[i+1]='\0';
	//printf("line length: %d\n",strlen(line));

	if (strlen(line) == 1)
	{
		return NULL;
	} else {
		return line;
	}
}

The current output of the program is as below

Total Channels: 8
channel: ABC
Time 18.00 18.30 19.00 19.30 20.00
Program Catalyst Report Dr Who: Underworld
-------------------------------------------------------------------------------
channel: Seven
Time 18.00 18.30 19.00 19.30 20.30
Program **ENDstaurant Rules
----------------------------------------------------------------------------------

As you can see, the program line is messed up while the time line is printed correctly. I want program line to be printed as time line.

Currently it seems it overwriting the data.

Originally Posted by quzah

I didn't ask what the current output was. I asked you to show me what you want it to be. You already showed what it was up above. You never told us what the program is supposed to output. Kinda hard to fix it when we don't know what it's supposed to look like.

Quzah.

Hi,

I guess, i was clear when I said my program line should look similar to my time line. Currently all the program names are getting overlapped with one another.

Anyway, following is what my program output should look like. Not showing the all time slots due to space constraints. This isn't any homework assignment and I am not a college student. . Just trying to develop my skills in C programming. I am not a full time programmer either.

Total Channels: 8
channel: ABC
Time 18.00 18.30 19.00 19.30
Program Dr Who: Underworld Collectors News The 7.30 Report
-------------------------------------------------------------------------------
channel: Seven
Time 18.00 18.30 19.00
Program Seven News Today Tonight Home and Away
----------------------------------------------------------------------------------

Hi,

I hate to say, but its still not working. Is this something compiler specific. If something works with you (donno which complier you used though) doesn't work with my compiler. I use gcc complier on linux.

Following is the code, incorporating the comments in last post from "Dave_Sinkula".

Code:

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

void getprograminfo(char *, char *, char *);
char * getline(FILE *);

int main(int argc, char *argv[])
{
	FILE *fp;
	int channels;
	char channelname[20];
	char *line;
	char linep[100];
	int i,a,len;
	char time[100];
	char program[100];
	char line1[1024];
	char line2[1024];
	char buffer[sizeof(line2)];
	int first;

	if (argc < 2)
	{
		printf(" USAGE: %s <filename>\n",argv[0]);
		exit(0);
	}


	if ((fp=fopen(argv[1],"r")) == NULL)
	{
		printf("can not open the file\n");
		exit(0);
	}

	fscanf(fp,"%d",&channels);

	printf("Total Channels: %d\n",channels);
	
	i = 0;
	first = 1;
	
	memset(line1,'\0',sizeof(line1));
	memset(line2,'\0',sizeof(line2));

	while ((fgets(linep,sizeof(linep),fp))!=NULL)
	{
		memset(channelname,'\0',20);		
		linep[strlen(linep)-1]= '\0';

		if ((line=strstr(linep,"=")) != NULL)
		{
			if (!first)
			{
				
				printf("%s\n%s\n",line1,line2);
				if (strlen(line1) > strlen(line2))
				{
					len = strlen(line1);
				} else {
					len = strlen(line2);
				}
				for (a=0;a<len;a++)
				{
					printf("-");
				}
				printf("\n");
				memset(line1,'\0',sizeof(line1));
				memset(line2,'\0',sizeof(line2));
				i=0;				
			} else {	
				first = 0;
			}
			strcpy(channelname,++line);
			printf("channel: %s\n",channelname);
			
		} else {
			memset(time,'\0',sizeof(time));
			memset(program,'\0',sizeof(program));
			getprograminfo(linep,time,program);
			
			if (i == 0)
			{
				sprintf(line1,"Time    %-15.15s ",time);
				sprintf(line2,"Program %-15.15s ",program);
			} else {
				
				strcpy(buffer, line1);
				memset(line1,'\0',sizeof(line1));
				sprintf(line1, "%s %-15.15s ", buffer, time);
				strcpy(buffer, line2);
				memset(line2,'\0',sizeof(line2));
				sprintf(line2, "%s %-15.15s ", buffer, program);
			}
			i++;
		}
	}

	printf("%s\n%s\n",line1,line2);
	if (strlen(line1) > strlen(line2))
	{
		len = strlen(line1);
	} else {
		len = strlen(line2);
	}
	for (a=0;a<len;a++)
	{
		printf("-");
	}
	printf("\n");

	fclose(fp);

	return 0;

}

void getprograminfo(char *line, char *time, char *program)
{
	int i,j;
	char tword[50];
	
	i=j=0;

	while (i<strlen(line))
	{
		if (line[i] == ' ')
		{
			tword[j]='\0';
			strcpy(time,tword);
			i++;
			strcpy(program,line+i);
			j=0;
			return;
		} else {
			tword[j]=line[i];
			i++;
			j++;
		}
	}
}

char * getline(FILE *fp)
{
	static char line[100];
	char ch;
	int i=0;

	memset(line,'\0',sizeof(line));
	
	while ((ch=fgetc(fp))!='\n')
	{
		if (ch == EOF)
		{
			return NULL;
		} else {
			line[i]=ch;
			i++;
		}
	}
	line[i+1]='\0';
	//printf("line length: %d\n",strlen(line));

	if (strlen(line) == 1)
	{
		return NULL;
	} else {
		return line;
	}
}

And here is the output (in code tags to preserve indentation)

Code:

Total Channels: 8
channel: ABC
Time                     18.00            18.30            19.00            19.30            20.00           
            The 7.30 Report  Catalystrwo  Collectors
-------------------------------------------------------------------------------------------------------------
channel: Seven
Time    18.00            18.30            19.00            19.30            20.30           
          aurant R  **END
--------------------------------------------------------------------------------------------

Well, i'll be damned. It worked just fine on my Windows PC. I have no clue whatsoever. I am using digital mars C compiler. Following was the program output

Code:

Total Channels: 8

channel: ABC
============
Time    18.00            18.30       19.00       19.30       20.00
Program Dr Who: Underwo  Collectors  News        The 7.30 R  Catalyst
------------------------------------------------------------------------

channel: Seven
==============
Time    18.00            18.30       19.00       19.30       20.30
Program Seven News       Today Toni  Home and A  My Restaur  **END
------------------------------------------------------------------------