如何将ac文件链接到两个可执行文件

Question

I have a file called wrapsock.c that has several wrapper functions for the socket.h header file. I have two executables, FTP_client and FTP_server who both need to use the wrapsock.c file. I am having trouble with my makefile to link the wrapsock.c file to both of these programs

Here is my makefile below:

all: ./bin/FTP_client ./bin/FTP_server

bin/FTP_client: main_client.o wrapsock.o
    gcc -o bin/FTP_client main_client.o wrapsock.o -lpthread -g
    mv main_client.o ./bin
    mv wrapsock.o ./bin

bin/FTP_server: main_server.o wrapsock.o
    gcc -o bin/FTP_server main_server.o wrapsock.o -lpthread -g
    mv main_server.o ./bin
    mv wrapsock.o ./bin

main_client.o: src/main_client.c
    gcc -c src/main_client.c -g

wrapsock.o: src/wrapsock.c src/wrapsock.h
    gcc -c src/wrapsock.c -g

main_server.o: src/main_server.c
    gcc -c src/main_server.c -g

clean:
    rm ./bin/*.o
    rm ./bin/FTP_client
    rm ./bin/FTP_server

This is the error I am receiving:

gcc -c src/main_client.c -g
gcc -c src/wrapsock.c -g
gcc -o bin/FTP_client main_client.o wrapsock.o -lpthread -g
mv main_client.o ./bin
mv wrapsock.o ./bin
gcc -o bin/FTP_server main_server.o wrapsock.o -lpthread -g
gcc: error: wrapsock.o: No such file or directory
make: *** [makefile:9: bin/FTP_server] Error 1

Answer 1

mv wrapsock.o ./bin
gcc -o bin/FTP_server main_server.o wrapsock.o -lpthread -g
gcc: error: wrapsock.o: No such file or directory

To move the object is not a good way, create the objects directly into the directory bin as you do for the executable :

all: ./bin/FTP_client ./bin/FTP_server

bin/FTP_client:  bin/main_client.o  bin/wrapsock.o
    gcc -o bin/FTP_client bin/main_client.o bin/wrapsock.o -lpthread -g

bin/FTP_server:  bin/main_server.o  bin/wrapsock.o
    gcc -o bin/FTP_server  bin/main_server.o  bin/wrapsock.o -lpthread -g

bin/main_client.o: src/main_client.c
    gcc -c src/main_client.c -g -o bin/main_client.o

bin/wrapsock.o: src/wrapsock.c src/wrapsock.h
    gcc -c src/wrapsock.c -g -o bin/wrapsock.o

bin/main_server.o: src/main_server.c
    gcc -c src/main_server.c -g -o bin/main_server.o

clean:
    rm ./bin/*.o
    rm ./bin/FTP_client
    rm ./bin/FTP_server

Answer 2

Not sure why are you moving the binary objects to bin/ , but after you've built your client target wrapsock.o is no longer in project root and resides in bin/ instead, so when server target gets its turn, gcc can no longer find it. I would just ditch the moves or if there is a reason for performing them, do so in a separate target that is done only after both binaries have been built (ie lists them as prerequisites).