-lsocket issues on Linux (RedHat 9)

[ZiaTioN]

I am writing this socket program in C and have run into an issue in my make file while using the -lsocket during compilation. I have to have this program compile on both Solaris and Linux. From what I have read -lsocket is not needed to be invoked during compilation on Linux but it does on Solaris? Is this true?

If this is true is there a way to determine in the make file what OS I am on and use -lsocket if on Solaris and not use it if on Linux? I know in perl I could simply compare the default variable $^O and since perl is built on C I would assume there is a way to perform this in native C. If so how could I do this?

[Void Main]

Yes, you could implement a check in your makefile using the "uname" system command:

Code: Select all

UNAME=$(shell uname)
LIBS=
ifeq ($(UNAME),SunOS)
LIBS+=-lsocket
endif
showme:
        @echo os=$(UNAME)
        @echo libs=$(LIBS)


NOTE: I think this will only work if you are using the GNU make on both Linux and Solaris. Is that what you are using?

[ZiaTioN]

Here is the make file in question:

CC= g++
CFLAGS= -g

# The -lsocket -lnsl are needed for the sockets.
# The -L/usr/ucblib -lucb gives location for the Berkeley library needed for
# the bcopy, bzero, and bcmp. The -R/usr/ucblib tells where to load
# the runtime library.


LIBS= -lnsl

all: udp_send udp_recv

udp_send: udp_send.c networks.h
$(CC) $(CFLAGS) -o udp_send udp_send.c $(LIBS)

udp_recv: udp_recv.c networks.h
$(CC) $(CFLAGS) -o udp_recv udp_recv.c $(LIBS)

clean:
rm udp_recv udp_send

I will try your suggestion though, thanx!

[Void Main]

Yes, this should work:

Code: Select all

CC= g++
CFLAGS= -g
 
# The -lsocket -lnsl are needed for the sockets.
# The -L/usr/ucblib -lucb gives location for the Berkeley library needed for
# the bcopy, bzero, and bcmp. The -R/usr/ucblib tells where to load
# the runtime library.
 
UNAME=$(shell uname)
LIBS= -lnsl
ifeq ($(UNAME),SunOS)
LIBS+= -lsocket
endif
 
all: udp_send udp_recv
 
udp_send: udp_send.c networks.h
        $(CC) $(CFLAGS) -o udp_send udp_send.c $(LIBS)
 
udp_recv: udp_recv.c networks.h
        $(CC) $(CFLAGS) -o udp_recv udp_recv.c $(LIBS)
 
clean:
        rm udp_recv udp_send


Again, assumes GNU make. You could also make two targets, one for Linux and one for Sun and then do a "make linux" or "make sun". The above way should be automatic though.