[Dev-C++] newbie with 'undefined reference to strcopy' only on linking files

I am using gcc on winNT, working with the CD of C programming 
accompanying Bruce Eckels' Thinking in C++.

I have a program with three files. I am not using "make"; I just 
compile them directly. All has worked well till now.
I compile my program to an object file ok (gcc -c employ2.c), but 
when I try to link it with the file with the main() method, I get 
the "undefined reference" error noted above. Here is my dos command 
line, showing the successful compilation to the .o file and the error 
that results both when trying to use the .o file and when 
recompiling  everyting from source:

C:\eckels>gcc -c employ2.c

C:\eckels>gcc -olab7 employ2.o lab7.c
employ2.o(.text+0x2a):employ2.c: undefined reference to `strcopy'
employ2.o(.text+0x40):employ2.c: undefined reference to `strcopy'
employ2.o(.text+0x56):employ2.c: undefined reference to `strcopy'
employ2.o(.text+0xfc):employ2.c: undefined reference to `strcopy'
employ2.o(.text+0x123):employ2.c: undefined reference to `strcopy'
employ2.o(.text+0x147):employ2.c: more undefined references to 
`strcopy' follow

C:\eckels>gcc -o lab7 employ2.c lab7.c
C:\TEMP\ccCqaaaa.o(.text+0x2a):employ2.c: undefined reference to 
`strcopy'
C:\TEMP\ccCqaaaa.o(.text+0x40):employ2.c: undefined reference to 
`strcopy'
C:\TEMP\ccCqaaaa.o(.text+0x56):employ2.c: undefined reference to 
`strcopy'
C:\TEMP\ccCqaaaa.o(.text+0xfc):employ2.c: undefined reference to 
`strcopy'
C:\TEMP\ccCqaaaa.o(.text+0x123):employ2.c: undefined reference to 
`strcopy'
C:\TEMP\ccCqaaaa.o(.text+0x147):employ2.c: more undefined references 
to `strcopy' follow

My header includes <string.h>. Here is my code, which is really 
eckels' code:
/* employ2.c*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "employ2.h"

struct Employee* createEmployee
        (char* last, 
        char* first, 
        char* title, 
        int sal)
{
    struct Employee* p = 
        malloc(sizeof(struct Employee));
    if (p != NULL)
    {
        strcopy(p->last, last);
        strcopy(p->first, first);
        strcopy(p->title, title);
        p->salary = sal;
    }
    return p;
}

char* getLast(struct Employee* emp)
{
    return emp ? emp->last : "";
}

char* getFirst(struct Employee* emp)
{
    return emp ? emp->first : "";
}

char* getTitle(struct Employee* emp)
{
    return emp ? emp->title : "";
}

int getSalary(struct Employee* emp)
{
    return emp->salary;
}

void setLast(struct Employee* emp, char* last)
{  
    if (emp != NULL)
    strcopy(emp->last, last);
}
void setFirst(struct Employee* emp, char* fir)
{
    if (emp != NULL)
    strcopy(emp->first, fir);
}

void setTitle(struct Employee* emp, char* title)
{
    if (emp != NULL)
    strcopy(emp->title, title);
}

void setSalary(struct Employee* emp, int sal)
{
    if (emp != NULL)
    strcopy(emp->salary, sal);
}

void printEmployee(struct Employee* emp)
{    
    putchar('{');
    
    if (emp != NULL)
        printf("%s\n%s\n%s\n%d\n", 
            emp->last,
             emp->first, 
            emp->title, 
            emp->salary);

    putchar('}');
}


What simple thing am I missing?