c codes need help,thanks

The [optional other stuff] was meant to say that you may have other options you want to pass to gcc - e.g. "-O3" to give you the highest level of optimization, or "-ansi" to ensure that your code is ANSI-C - there are literally hundreds of different options that gcc can be given. A text-file is not one of those. The information that your code needs to open "myfile.txt" is already in the source code.

It also says:
10-2.c:10: warning: empty body in an if-statement

What do you think that means?

--
Mats

Quote:

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Originally Posted by matsp

The [optional other stuff] was meant to say that you may have other options you want to pass to gcc - e.g. "-O3" to give you the highest level of optimization, or "-ansi" to ensure that your code is ANSI-C - there are literally hundreds of different options that gcc can be given. A text-file is not one of those. The information that your code needs to open "myfile.txt" is already in the source code.

It also says:
10-2.c:10: warning: empty body in an if-statement

What do you think that means?

--
Mats

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thanks for you explanation, i have to learn much more things to know that.

i don't know what that warning means, does is mean the if-statement is not correct or in vain?

the c textbook has that statement exactly.

Quote:

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Originally Posted by hth373737

thanks for you explanation, i have to learn much more things to know that.

i don't know what that warning means, does is mean the if-statement is not correct or in vain?

the c textbook has that statement exactly.

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Really?!?! Are you sure it has the semicolon before the brace?

--
Mats

>> i don't know what that warning means, does is mean the if-statement is not correct or in vain?

In vain, I believe.

>> the c textbook has that statement exactly.

Nonetheless, you should know what effect a semicolen has there.

Quote:

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Originally Posted by Sebastiani

>> i don't know what that warning means, does is mean the if-statement is not correct or in vain?

In vain, I believe.

>> the c textbook has that statement exactly.

Nonetheless, you should know what effect a semicolen has there.

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Quote:

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Originally Posted by matsp

Really?!?! Are you sure it has the semicolon before the brace?

--
Mats

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Code:

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#include <stdio.h>
#include <stdlib.h>
int main(void)
{
        FILE *fp,*fw;// declaring file pointers.
        double val;
        char ch;
        int new;        // new for integer part.
        if((fp = fopen("myfile.txt","r"))==NULL)
        {
        printf("sorry,cannot open the file\n");
        exit(0);
        }
    fw = fopen("mynewfile.txt","w");
        do{
                fscanf(fp, "%lf", &val); //read real number from the file.
                ch = getc(fp);          //get the following number after the realnumber.
                new=val;                //pass numbers to integer form.cos new is defined intefer
                fprintf(fw,"%d",new);
                printf("%lf",val);    //print out the real number.
                printf("%d",new);      //print out the integer number.
               
                if ( ch=='\n' || ch==EOF )//determin to end the progress if there is a '\n' char or End Of File.
                        printf("\n");  // switch to next line.
        }while ( ch != EOF );
        fclose(fp);
        return 0;
}

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here is the exact codes, anything wrong? i cannot find it...

Code:

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#include <stdio.h>
#include <stdlib.h>
int main(void)
{
        FILE *fp,*fw;// declaring file pointers.
        double val;
        char ch;
        int new;        // new for integer part.
        if((fp = fopen("myfile.txt","r"))==NULL)
        {
        printf("sorry,cannot open the file\n");
        exit(0);
        }
    fw = fopen("mynewfile.txt","w"); /* not checking return value */
        do{
                fscanf(fp, "&#37;lf", &val); /* not checking return value */
                ch = getc(fp);          /* ch should be int */
                new=val;                //pass numbers to integer form.cos new is defined intefer
                fprintf(fw,"%d",new); /* don't you need space between numbers? */
                printf("%lf",val);    //print out the real number.
                printf("%d",new);      //print out the integer number.
               
                if ( ch=='\n' || ch==EOF )/* ch should be int to correctly compare with EOF */
                        printf("\n");  // switch to next line.
        }while ( ch != EOF );
        fclose(fp); /* what about closing the over file as well ? */
        return 0;
}

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Quote:

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Originally Posted by vart

Code:

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#include <stdio.h>
#include <stdlib.h>
int main(void)
{
        FILE *fp,*fw;// declaring file pointers.
        double val;
        char ch;
        int new;        // new for integer part.
        if((fp = fopen("myfile.txt","r"))==NULL)
        {
        printf("sorry,cannot open the file\n");
        exit(0);
        }
    fw = fopen("mynewfile.txt","w"); /* not checking return value */
        do{
                fscanf(fp, "%lf", &val); /* not checking return value */
                ch = getc(fp);          /* ch should be int */
                new=val;                //pass numbers to integer form.cos new is defined intefer
                fprintf(fw,"%d",new); /* don't you need space between numbers? */
                printf("%lf",val);    //print out the real number.
                printf("%d",new);      //print out the integer number.
               
                if ( ch=='\n' || ch==EOF )/* ch should be int to correctly compare with EOF */
                        printf("\n");  // switch to next line.
        }while ( ch != EOF );
        fclose(fp); /* what about closing the over file as well ? */
        return 0;
}

---

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Code:

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#include <stdio.h>
#include <stdlib.h>
int main(void)
{
        FILE *fp,*fw;// declaring file pointers.
        double val;
        int ch;
        int new;        // new for integer part.
        int i=0;
        if((fp = fopen("a.txt","r"))==NULL)
        {
        printf("sorry,cannot open the file\n");
        exit(0);
        }
    if((fw = fopen("mynewfile.txt","w"))==NULL)
        do{
                fscanf(fp, "%lf", &val); //read real number from the file. i dont know how the check the return number
                ch = getc(fp);          //get the following number after the realnumber.
                new=val;                //pass numbers to integer form.cos new is defined intefer
                fprintf(fw,"%d",new);// the numbers are arranged in conclum 3*5, with a space to separate them.
                printf("%lf",val);    //print out the real number.
                printf("%d",new);      //print out the integer number.
                i++;
               
                if ( i%5==0 || ch==EOF )//determin to end the progress if there is a '\n' char or End Of File.
                        fprintf(fw,"\n");  // switch to next line.
        }while ( ch != EOF );
        fclose(fp);// what the matter?i just want to close the file
        return 0;
}

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