\definecolor{middlegray}{rgb}{0.5,0.5,0.5}
\definecolor{orange}{rgb}{0.8,0.3,0.3}
\definecolor{yac}{rgb}{0.6,0.6,0.1}
\lstset{language=C}
\lstset{numbers=left, numberstyle=\tiny, numbersep=5pt, showspaces=false}
\lstset{keywordstyle=\color{orange}\bfseries\emph, stringstyle=\color{yac}, commentstyle=\color{middlegray}\ttfamily}
\lstset{escapechar=\§,numbers=left}

\begin{lstlisting}[language=C, firstnumber=1]
#define _STRUCTURED_PROC 1
#define __EXTENSIONS__
#include <sys/procfs.h>
#undef __EXTENSIONS__
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include "errorhandler.h"

int main(int argc, char *argv[]) {
    char pfad[255];
    struct pstatus *status;
    FILE *fh;
    status = malloc(sizeof(struct pstatus));

    if (status == NULL) {
        error_exit("Malloc fehler", 3);
    }
    if (argc != 2) {
        error_exit("Es wird genau ein Parameter benoetigt.", 2);
    }

    if (strlen(argv[1]) > 200) {
        error_exit("Die ID ist zu gross", 4);
    }

    sprintf(pfad, "/proc/%s/status", argv[1]);
    fh = fopen(pfad, "rb");

    if (fh ==  NULL) {
        error_exit("Fopen fehler", 5);
    }
    if (
            fread(status, (size_t)1, sizeof(struct pstatus), fh)
            != sizeof(struct pstatus)
        ) {
        error_exit("Fread fehler, Datei zu klein", 6);
    }
    fclose(fh);



    printf("Prozessid: \t %lu \n", (unsigned long)status->pr_pid);
    printf("Parent Prozessid: \t %lu \n", (unsigned long)status->pr_ppid);
    printf("Leichtgewichtige Prozesse: \t %d \n", (int)status->pr_nlwp);
    printf("Stackwerte: \n");
    printf("Heapstart: %p\n", (void *)status->pr_brkbase);
    printf("Heapgroesse: %d\n", (int)status->pr_brksize);
    printf("Startadresse: %p\n", (void *)status->pr_stkbase);
    printf("Groeße: %d\n", (int)status->pr_stksize);

    free(status);

    return 0;
}

\end{lstlisting}