Sort of a column in two dimensional array. Usage example included. I will add documentation someday.

columnSort.c

#include <stdio.h>
#include <stdlib.h>
#define COLUMNS_NO 3

void sort_column(char matrix[][COLUMNS_NO], int lines_no, int col) {
    int i, j;
    char temp;

    for (i = 0; i < lines_no - 1; i++) {
        for (j = 0; j < lines_no - 1 - i; j++) {
            if (matrix[j][col] > matrix[j + 1][col]) {
                temp = matrix[j][col];
                matrix[j][col] = matrix[j + 1][col];
                matrix[j + 1][col] = temp;
            }
        }
    }
}

int main() {
    char matrix[4][COLUMNS_NO] = {
        {'f', 'j', 'h'},
        {'w', 'g', 'k'},
        {'o', 'c', 'l'},
        {'d', 'a', 'i'}
    };
    int i, j;
     printf("Before Sort:\n");
     for (i = 0; i < 4; i++) {
        for (j = 0; j < 3; j++) {
            printf("%3c", matrix[i][j]);
        }
        printf("\n");
    }
    sort_column(matrix, 4, 1);
    printf("After Sort:\n");
    for (i = 0; i < 4; i++) {
        for (j = 0; j < 3; j++) {
            printf("%3c", matrix[i][j]);
        }
        printf("\n");
    }
    exit(EXIT_SUCCESS);
}