Does not build on macOS as unistd.h is not included

[CodingMarkus]

Should fail the same way on many other POSIX systems as unlink and symlink are documented to be declared in unistd.h which isn't ever included.

troff_generator.c:225:13: error: implicit declaration of function 'unlink' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
            unlink( buf );
            ^

troff_generator.c:226:13: error: implicit declaration of function 'symlink' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
            symlink( basename( manpage ), buf );
            ^

See POSIX reference to confirm that those functions are supposed to be declared by unistd.h

Also see man page:

SYNOPSIS
     #include <unistd.h>

     int
     unlink(const char *path);

Source :man 2 unlink

Note that sys/unistd.h is no official header, neither by C nor by POSIX standard, you should never be required to include that one. Same holds true for sys/param.h. These headers are automatically included for you if you included the correct standard headers.

[remkos]

Compiling on macOS worked for me by replacing <sys/unistd.h> by <unistd.h>