Thread: Finished my homework on cat

I made a cat which takes option flag input as well. It's fairly basic and pretty poor performance.

I only have one minor bug that I can find. If using the "-e" flag and they're multiple newlines in a row, it'll print this as output:

$

$

$

$

Instead of just:

$
$
$
$

Here's the code:

Code:

#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>


int main(int argc, char *argv[]) {
    int8_t FileData, FlagIndicator, sFlag, eFlag, tFlag, seFlag;
    uint64_t NewLineCounter, TabCounter;
    FILE *fp = NULL;
    
    sFlag = eFlag = tFlag = seFlag = 0;
    
    if(argc < 2) {
        fprintf(stderr, "Enter a file name\n");
        return 1;
    }
    
    while((FlagIndicator = getopt(argc, argv, "set")) != -1)
        switch(FlagIndicator) {
            case 's':
                sFlag = 1;
                break;
                
            case 'e':
                eFlag = 1;
                break;
                
            case 't':
                tFlag = 1;
                break;
                
            default:
                (void)fprintf(stderr, "Usage: [-set] [file...]\n");
                return 1;
        }
    
    if(sFlag || eFlag || tFlag)
        fp = fopen(argv[2], "r");
    
    else
        fp = fopen(argv[1], "r");
    
    if(sFlag && eFlag)
        seFlag = 1;
    
    if(fp == NULL) {
        fprintf(stderr, "No file found.\n");
        return 1;
    }
    
    FileData = getc(fp);
    
    while(1) {
        if(seFlag) {
            for(NewLineCounter = 0; FileData == '\n'; NewLineCounter++) {
                if(NewLineCounter < 2)
                    printf("$\n");
                
                FileData = getc(fp);
            }
        }
        
        if(sFlag && !seFlag) {
            for(NewLineCounter = 0; FileData == '\n'; NewLineCounter++) {
                if(NewLineCounter < 2)
                    printf("\n");
                
                FileData = getc(fp);
            }
        }
        
        if(eFlag && !seFlag) {
            if(FileData == '\n') {
                printf("$%c", FileData);
                
                FileData = getc(fp);
            }
        }
        
        if(tFlag) {
            for(TabCounter = 0; FileData == '\t'; TabCounter++) {
                printf("^I");
                
                FileData = getc(fp);
            }
        }
        
        if(FileData == EOF)
            break;
        
        printf("%c", FileData);
        
        FileData = getc(fp);
    }
    
    fclose(fp);
    
    return 0;
}