macOS how can i open a data file to run this program?

[manee]

#include <stdio.h>

#define EOF -1


main()
{
    int count,letter;
    system("pwd");
    count=0;
    letter= getchar();
    
    while(letter!= EOF)
    {
        if(letter=='e')
            ++count;
        letter=getchar();
    }
    printf("frequency %d\n",count);
}

this program counts the number of 'e's on a text i saved under a text file.I want to know how i can open that file. the program name is com1 and the file name is file1.

com1<file1 doesn't work

 

[subsonix]

Redirecting stdin works, you just need to provide the path to com1. For your current directory use ./com1 < file

You shouldn't define EOF as it's a predefined constant, also main should return int.

#include <stdio.h>

int main()
{
    int count,letter;
    system("pwd");
    count=0;
    letter= getchar();

    while(letter != EOF)
    {
        if(letter=='e')
            ++count;
        letter=getchar();
    }

    printf("frequency %d\n",count);

    return 0;
}

You can use fopen and fread, fgetc, fgets, fscanf and so on to read from a file in the program.

 

[willieva]

Please post the output of your run. Except for a spurious system call and redefining EOF, everything looks fine.

Make sue both com1 and file1 are in the current directory:
ls com1 file1

Perhaps '.' isn't in your path? Try running it like
./com1 < file1

 

[chown33]

com1<file1 doesn't work

Always post any error messages that appear when it doesn't work. If you got no error messages, then say that.

Posting error messages tells us what actually happened. Otherwise we're just guessing. "It doesn't work" doesn't describe what happened.

Here are four Rules of Thumb for posting:
1. Be specific.
2. Post your code.
3. Describe what you expected to happen.
4. Describe what actually happened.