using external libraries: undefined reference

[Inquirer]

It seems these "undefined reverence" things are really plaguing me. Now, i am writing a cryotographic prgram, and i am going to be implementing an MD5 hash, so i downloaded OpenSSH and installed it to ~/usr/local/ssl. Here is the command that is being executed, the errors, the filenames, and the makefile.

Errors:

$ g++ -I/home/ethereal/usr/local/ssl/include -L/home/et
hereal/usr/local/ssl/lib -a ~/usr/local/ssl/lib/libcrypto.a -lcrypto efcrypt.o -
o efcrypt
efcrypt.o: In function `main':
efcrypt.o(.text+0x2f): undefined reference to `MD5'
collect2: ld returned 1 exit status

the files: (you'll have to trust me about whats in ./include)

$ ls -lA ~/usr/local/ssl/include ~/usr/local/ssl/lib
/home/ethereal/usr/local/ssl/include:
total 4
drwxrwxr-x    2 ethereal ethereal     4096 May  9 22:55 openssl

/home/ethereal/usr/local/ssl/lib:
total 1868
-rw-r--r--    1 ethereal ethereal  1641636 May  9 22:55 libcrypto.a
-rw-r--r--    1 ethereal ethereal   255532 May  9 22:55 libssl.a
drwxrwxr-x    2 ethereal ethereal     4096 May  9 22:55 pkgconfig

makefile:

# Makefile for EFcrypt

CC = g++
CFLAGS = -I/home/ethereal/usr/local/ssl/include -L/home/ethereal/usr/local/ssl/lib -lcrypto

efcrypt : efcrypt.o
        $(CC) $(CFLAGS) efcrypt.o -o efcrypt

efcrypt.o : efcrypt.cpp
        $(CC) $(CFLAGS) -c efcrypt.cpp

clean :
        rm -f *.o

[Inquirer]

Wow. So simple. Thanks! i'll have to remember that.

~Inquirer

[manio]

Hello
i have identical problem - but i can't see a solution here
I have also: "undefined reference to `MD5'", i'm also using g++.
I thought, that it is an old openssl, so i downloaded the newest version 0.9.8a (i've removed the old) - doesn't work
So i even updated the gcc to version 3.3.2 - also doesn't work.
When i look inside the .o file i can see that name MD5 is inside, also i can see the same name in /usr/local/lib/libcrypto.a
Besides - it compiles successfully on other linux box, but not on my debian.
please help - i am really helpless

regards

[dwks]

Maybe you need something like

g++ file.cpp -o file -l/usr/local/lib/libcrypto.a

I don't know the exact syntax.

[manio]

The problem was: i need to pass a library name just after the .o files - not before like it did. Static libraries need that - when using shared - it shouldn't matter.