strpbrk.c


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

char **redir_chop(const char *, const char);

/* chops a line into 2 string that are seperated by redir_delim  */
char **redir_chop(const char *line, const char redir_delim)
{
    if (!line)
        return NULL;

    const char *delim = &redir_delim;

    char *pipe_redir = strpbrk(line, delim);
    if (pipe_redir == NULL)
        return NULL;

    size_t redir_delta = pipe_redir - line;
    char **ret = (char **) malloc(sizeof(char *) * 2);
    ret[0] = (char *) malloc(sizeof(char) * 256 * 2);
    ret[1] = ret[0] + 256;

    char *former = ret[0];
    char *latter = ret[1];

    strncpy(former, line, redir_delta);
    former[redir_delta] ='\0';

    /* delete spaces at the end of former string */
    int i = strlen(former) - 1;
    while (former[i] == ' ')
        former[i--] = '\0';

    /* skip spaces in latter string and then copy over */
    int j = redir_delta;
    while (line[++j] == ' ')
        ;
    strncpy(latter, line+j, (line + strlen(line)) - pipe_redir);

    return ret;
}

int main(int argc, char *argv[])
{
    const char *line = "ls -1 -al > filename.txt";
    char **chopped = redir_chop(line, '>');
 
    printf("former string: \"%s\"\n", chopped[0]);
    printf("latter string: \"%s\"\n", chopped[1]);

    free(chopped);
    
    return 0;
}