errno : C Error Handling

Whatever programming you are doing. It's nice to have a feedback if something goes wrong in your program. Basically a c program would capture error message value generated by system's environment. Bellow is a rudimentary function that capture error handling.
#include "error.h"
#include "errno.h"
#include "stdio.h"

void errordisplay(int error)
{
switch (error)
{
case E2BIG : printf("E2BIG");break;
case EACCES : printf("EACCES");break;
case EADDRINUSE : printf("EADDRINUSE");break;
case EADDRNOTAVAIL : printf("EADDRNOTAVAIL");break;
case EAFNOSUPPORT : printf("EAFNOSUPPORT");break;
/*case EAGAIN : printf("EAGAIN");break;*/
case EALREADY : printf("EALREADY");break;
case EBADE : printf("EBADE");break;
case EBADF : printf("EBADF");break;
case EBADFD : printf("EBADFD");break;
case EBADMSG : printf("EBADMSG");break;
case EBADR : printf("EBADR");break;
case EBADRQC : printf("EBADRQC");break;
case EBADSLT : printf("EBADSLT");break;
case EBUSY : printf("EBUSY");break;
case ECANCELED : printf("ECANCELED");break;
case ECHILD : printf("ECHILD");break;
case ECHRNG : printf("ECHRNG");break;
case ECOMM : printf("ECOMM");break;
case ECONNABORTED : printf("ECONNABORTED");break;
case ECONNREFUSED : printf("ECONNREFUSED");break;
case ECONNRESET : printf("ECONNRESET");break;
/*case EDEADLK : printf("EDEADLK");break;*/
case EDEADLOCK : printf("EDEADLOCK");break;
case EDESTADDRREQ : printf("EDESTADDRREQ");break;
case EDOM : printf("EDOM");break;
case EDQUOT : printf("EDQUOT");break;
case EEXIST : printf("EEXIST");break;
case EFAULT : printf("EFAULT");break;
case EFBIG : printf("EFBIG");break;
case EHOSTDOWN : printf("EHOSTDOWN");break;
case EHOSTUNREACH : printf("EHOSTUNREACH");break;
case EIDRM : printf("EIDRM");break;
case EILSEQ : printf("EILSEQ");break;
case EINPROGRESS : printf("EINPROGRESS");break;
case EINTR : printf("EINTR");break;
case EINVAL : printf("EINVAL");break;
case EIO : printf("EIO");break;
case EISCONN : printf("EISCONN");break;
case EISDIR : printf("EISDIR");break;
case EISNAM : printf("EISNAM");break;
case EKEYEXPIRED : printf("EKEYEXPIRED");break;
case EKEYREJECTED : printf("EKEYREJECTED");break;
case EKEYREVOKED : printf("EKEYREVOKED");break;
case EL2HLT : printf("EL2HLT");break;
case EL2NSYNC : printf("EL2NSYNC");break;
case EL3HLT : printf("EL3HLT");break;
case EL3RST : printf("EL3RST");break;
case ELIBACC : printf("ELIBACC");break;
case ELIBBAD : printf("ELIBBAD");break;
case ELIBMAX : printf("ELIBMAX");break;
case ELIBSCN : printf("ELIBSCN");break;
case ELIBEXEC : printf("ELIBEXEC");break;
case ELOOP : printf("ELOOP");break;
case EMEDIUMTYPE : printf("EMEDIUMTYPE");break;
case EMFILE : printf("EMFILE");break;
case EMLINK : printf("EMLINK");break;
case EMSGSIZE : printf("EMSGSIZE");break;
case EMULTIHOP : printf("EMULTIHOP");break;
case ENAMETOOLONG : printf("ENAMETOOLONG");break;
case ENETDOWN : printf("ENETDOWN");break;
case ENETRESET : printf("ENETRESET");break;
case ENETUNREACH : printf("ENETUNREACH");break;
case ENFILE : printf("ENFILE");break;
case ENOBUFS : printf("ENOBUFS");break;
case ENODATA : printf("ENODATA");break;
case ENODEV : printf("ENODEV");break;
case ENOENT : printf("ENOENT");break;
case ENOEXEC : printf("ENOEXEC");break;
case ENOKEY : printf("ENOKEY");break;
case ENOLCK : printf("ENOLCK");break;
case ENOLINK : printf("ENOLINK");break;
case ENOMEDIUM : printf("ENOMEDIUM");break;
case ENOMEM : printf("ENOMEM");break;
case ENOMSG : printf("ENOMSG");break;
case ENONET : printf("ENONET");break;
case ENOPKG : printf("ENOPKG");break;
case ENOPROTOOPT : printf("ENOPROTOOPT");break;
case ENOSPC : printf("ENOSPC");break;
case ENOSR : printf("ENOSR");break;
case ENOSTR : printf("ENOSTR");break;
case ENOSYS : printf("ENOSYS");break;
case ENOTBLK : printf("ENOTBLK");break;
case ENOTCONN : printf("ENOTCONN");break;
case ENOTDIR : printf("ENOTDIR");break;
case ENOTEMPTY : printf("ENOTEMPTY");break;
case ENOTSOCK : printf("ENOTSOCK");break;
/*case ENOTSUP : printf("ENOTSUP");break;*/
case ENOTTY : printf("ENOTTY");break;
case ENOTUNIQ : printf("ENOTUNIQ");break;
case ENXIO : printf("ENXIO");break;
case EOPNOTSUPP : printf("EOPNOTSUPP");break;
case EOVERFLOW : printf("EOVERFLOW");break;
case EPERM : printf("EPERM");break;
case EPFNOSUPPORT : printf("EPFNOSUPPORT");break;
case EPIPE : printf("EPIPE");break;
case EPROTO : printf("EPROTO");break;
case EPROTONOSUPPORT : printf("EPROTONOSUPPORT");break;
case EPROTOTYPE : printf("EPROTOTYPE");break;
case ERANGE : printf("ERANGE");break;
case EREMCHG : printf("EREMCHG");break;
case EREMOTE : printf("EREMOTE");break;
case EREMOTEIO : printf("EREMOTEIO");break;
case ERESTART : printf("ERESTART");break;
case EROFS : printf("EROFS");break;
case ESHUTDOWN : printf("ESHUTDOWN");break;
case ESPIPE : printf("ESPIPE");break;
case ESOCKTNOSUPPORT : printf("ESOCKTNOSUPPORT");break;
case ESRCH : printf("ESRCH");break;
case ESTALE : printf("ESTALE");break;
case ESTRPIPE : printf("ESTRPIPE");break;
case ETIME : printf("ETIME");break;
case ETIMEDOUT : printf("ETIMEDOUT");break;
case ETXTBSY : printf("ETXTBSY");break;
case EUCLEAN : printf("EUCLEAN");break;
case EUNATCH : printf("EUNATCH");break;
case EUSERS : printf("EUSERS");break;
case EWOULDBLOCK : printf("EWOULDBLOCK");break;
case EXDEV : printf("EXDEV");break;
case EXFULL : printf("EXFULL");break;
}
}

int main(void)
{
int err;
FILE *fp = NULL;
if (fp=fopen("SSS","r")==NULL)
{
err = errno;
}
errordisplay(err);
return 0;
}

After compiling and running this program you notice that it will display the error message, wich is originally is an integer value. I copied, pasted and edited that error messages from errno.h header file (/usr/include/errno.h) :

browse@joko-desktop:~/Desktop$ gcc -o errprog.o errprog.c
errprog.c: In function ‘main’:
errprog.c:135: warning: assignment makes pointer from integer without a cast
browse@joko-desktop:~/Desktop$ ./errprog.o
ENOENTbrowse@joko-desktop:~/Desktop$

Hopefully this will help you in catching logical error in long programs that have many interfaces to another entities. WISH YOU LUCK