How do I link BSD C functions to my executable?


To link executables using BSD compatibility functions (these are functions
in the 3B man pages) add the library libucbc (-lucbc).  The following is an
example done in C.

        $ cat a.c
        #include <sys/wait.h>
        #include <sys/time.h>
        #include <sys/resource.h>

        main()
        {
                wait3(NULL,0,NULL);
                sigblock(0xffffffff);
        }
        $ cc a.c
        Undefined                       first referenced
         symbol                             in file
        sigblock                            a.o
        wait3                               a.o
        ld: a.out: fatal error: Symbol referencing errors. No output written to a.out
        cc: ERROR: Errors in the ld pass, status = 1
        $

These function are undefined because the ucb C library is not included.

        $ cc a.c -lucbc
        $ 

With the -lucbc option added we get no error messages.

Running "man -k 3B" will show all the BSD functions.

        $ man -k 3B
        bstring: bcopy, bcmp, bzero (3B)    - (BSD) bit and byte string operations
        dbm:  dbminit, dbmclose, fetch, store, delete, firstkey, nextkey (3B)   - (BSD) data base subroutines
        ...
        usleep (3B)             - (BSD) suspend execution for interval in microseconds
        utimes (3B)             - (BSD) set file times
        wait: wait3, WIFSTOPPED, WIFSIGNALED, WIFEXITED (3B)    - (BSD) wait for process to \%terminate or stop


For more information see cc(1).