Reading whole input instead of single line

Question

I have written program which changes from lowercase letter to uppercase. Problem is, i dont know how to make it read whole text instead of one line. Program returns output after pressing enter and I want it to do so, after CTRL+Z.

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


void makeUpper(char *s) {
    int i;
    for(i = 0; s[i] != '\0'; i++){
        s[i] = toupper(s[i]);
    }
    printf("%s", s);
}


int main() {
    char string[1000];

    fgets(string, 1000, stdin);

    makeUpper(string);
    return 0;
}

Various options here: http://stackoverflow.com/a/1836454/694576 — alk, Nov 08 '16 at 09:38
@Rafal I mean to not stop accepting data after pressing enter, just after CTRL+Z in console — NouName, Nov 08 '16 at 09:42
In on windows. this probably does not work. The win console accepts Ctrl-Z as EOF only if entered as 1st input on a line. — alk, Nov 08 '16 at 09:51

score 3 · Answer 1 · answered Nov 08 '16 at 09:57

3

just put your fgets(string, 1000, stdin) into a while loop.here is the solution

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

void makeUpper(char *s) {
    int i;
    for(i = 0; s[i] != '\0'; i++){
        s[i] = toupper(s[i]);
    }
    printf("%s", s);
}


int main() {
    char string[1000];

    while(fgets(string, 1000, stdin)!=NULL)//for getting input untill pressing CTRL+Z.
    {
        makeUpper(string);
    }


    return 0;
}

answered Nov 08 '16 at 09:57

Real73

480
4
12

Did you test this on Windows? – alk Nov 08 '16 at 10:00
@alk yes!! first i try in my windows it works fine then post here :). – Real73 Nov 08 '16 at 10:03
Using which compiler? – alk Nov 08 '16 at 10:04
BTW, the code misses to include ``. – alk Nov 08 '16 at 10:04
This is a good solution. But one problem I see is that this will do the lower-to-upper conversion *immediately* after reading a line whereas OP seems to need to do the conversion as a whole. – P.P Nov 08 '16 at 10:11
@alk without `` it works for me on version `mingw32-gcc.exe` of GNU GCC COMPILER . i just try to figure out taking input untill pressing CTRL+Z @usr – Real73 Nov 08 '16 at 10:18

score 2 · Accepted Answer · answered Nov 08 '16 at 09:51

2

fgets() will stop once it encounters a newline. So, you can't workaround it to read multiple lines. So, you'll have to look at alternatives.

One way is is use getchar() is a loop and read as long as there's a room in the buffer or EOF is received.:

int main(void) {

    char string[1000];
    size_t i = 0;

    do {
        int ch = getchar();
        if (ch == EOF) break;
        string[i] = ch;
        i++;
    } while (i < sizeof string - 1);
    string[i] = 0;

    makeUpper(string);
    return 0;
}

Remember, ctrl+Z works on Windows (to send EOF). On *nix-like systems, you'll have to use Ctrl+D to send EOF.

answered Nov 08 '16 at 09:51

P.P

106,931
18
154
210

"*`fgets()` will stop once it encounters a newline.*" It might be worth mentioning that this is Windows specific. On IX'ish systems `Ctrl-D` to indicate `EOF` very well ends `fgets()`. – alk Nov 08 '16 at 09:53
I wasn't referring to the `D``Z`difference, but to the fact that `Ctrl-Z` on windows would not end `fgets()` if already some input was given, whereas it would on UNIX (for `Ctrl-D` in this case). – alk Nov 08 '16 at 09:59
Sending EOF by whatever OS-specific means will end fgets(). But AFAICT, OP's problem is *not* detecting EOF but to read multiple lines (basically OP is handicapped by the fact that `fgets()` stops at a newline whereas he wants to read more until EOF is sent explicitly by him). – P.P Nov 08 '16 at 10:07

Reading whole input instead of single line

2 Answers2