ex1

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

int main(int argc, char *argv[]){
    char input[10], output[10], ch;
    int smallch=0, bigch=0, digits=0, apparitions=0, total=0;
    int f1,f2;
    strcpy(input, argv[1]);
    strcpy(output, argv[2]);
    ch=argv[3][0];
    f1=open(argv[1],O_RDONLY);

    f2=open(argv[2],O_WRONLY);
    if(f1==-1)
        printf("cannot open input file\n");
    if(f1==-1)
        printf("cannot open output file\n");
    //read file

    char car;
    int r;
    while((r=read(f1,&car,1))>0){
        if(car>=97&&car<=122){
            smallch++;
        }
        else if(car>=65&&car<=90){
            bigch++;
        }
        else if(car>=48&&car<=57){
            digits++;
        }
        if(car==ch)
            apparitions++;
        total++;
    }

    //printf("%d %d %d %d", smallch,bigch,apparitions,total);
    char string[50],aux[5];
    int w;
    itoa(smallch,aux,10);
    strcpy(string,"numar litere mici: ");
    strcat(string, aux);
    strcat(string, "\n");
    w=write(f2,string,strlen(string));

    itoa(bigch,aux,10);
    strcpy(string,"numar litere mari: ");
    strcat(string, aux);
    strcat(string, "\n");
    w=write(f2,string,strlen(string));

    itoa(digits,aux,10);
    strcpy(string,"numar cifre: ");
    strcat(string, aux);
    strcat(string, "\n");
    w=write(f2,string,strlen(string));

    itoa(apparitions,aux,10);
    strcpy(string,"numar aparitii caracter: ");
    strcat(string, aux);
    strcat(string, "\n");
    w=write(f2,string,strlen(string));

    itoa(total,aux,10);
    strcpy(string,"dimensiune fisier: ");
    strcat(string, aux);
    w=write(f2,string,strlen(string));

    if(close(f1)<0){
        perror("eroare inchidere fisier citire");
        exit(1);
    }
    if(close(f2)<0){
        perror("eroare inchidere fisier scriere");
        exit(1);
    }
    //f=close(f1);
    //g=close(f2);

    //return 0;
}