尽管我已经安装了libpcap，但遇到“找不到lpcap”错误

Question

Facing error with "cannot find lpcap" for make command for some package, although I have already installed libpcap.devel.

go build -i -ldflags "-linkmode external -extldflags -static -X main.version=git-6e3f8a1c7a0a" -tags netgo -o prog/weaver/weaver ./prog/weaver
# github.com/weaveworks/weave/prog/weaver
/go/pkg/tool/linux_s390x/link: running s390x-linux-gnu-gcc failed: exit status 1
/usr/lib64/gcc/s390x-suse-linux/7/../../../../s390x-suse-linux/bin/ld: cannot find -lpcap
/tmp/go-link-225248852/000015.o: In function `mygetgrouplist':
/tmp/workdir/go/src/os/user/getgrouplist_unix.go:15: warning: Using 'getgrouplist' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking

I can see the .so files at

/usr/lib64 # ls | grep pcap

libpcap.so

libpcap.so.1

libpcap.so.1.8.1

Answer 1

The openSUSE libpcap development RPm does not provide a static libpcap.a, so you cannot statically link libpcap unless you are able to build the static library from source (and any others to which the same applies).

Removing -static from your -ldflags would avoid this problem, if it is an option for you to link your go program dynamically.