$ strace -f nc -v google.com 80
execve("/usr/bin/nc", ["nc", "-v", "google.com", "80"], [/* 35 vars */]) = 0
brk(0) = 0xe9c000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4486a8d000
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=36889, ...}) = 0
mmap(NULL, 36889, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f4486a83000
close(3) = 0
open("/usr/lib64/libglib-2.0.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0 \242\1\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=1212360, ...}) = 0
mmap(NULL, 3308288, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f4486545000
mprotect(0x7f448666b000, 2097152, PROT_NONE) = 0
mmap(0x7f448686b000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x126000) = 0x7f448686b000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P%\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=2173360, ...}) = 0
mmap(NULL, 3981792, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f4486178000
mprotect(0x7f448633a000, 2097152, PROT_NONE) = 0
mmap(0x7f448653a000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c2000) = 0x7f448653a000
mmap(0x7f4486540000, 16864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f4486540000
close(3) = 0
open("/lib64/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\300l\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=144552, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4486a82000
mmap(NULL, 2208904, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f4485f5c000
mprotect(0x7f4485f73000, 2093056, PROT_NONE) = 0
mmap(0x7f4486172000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x16000) = 0x7f4486172000
mmap(0x7f4486174000, 13448, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f4486174000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4486a81000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f4486a7f000
arch_prctl(ARCH_SET_FS, 0x7f4486a7f740) = 0
mprotect(0x7f448653a000, 16384, PROT_READ) = 0
mprotect(0x7f4486172000, 4096, PROT_READ) = 0
mprotect(0x7f4486a8e000, 4096, PROT_READ) = 0
munmap(0x7f4486a83000, 36889) = 0
set_tid_address(0x7f4486a7fa10) = 14727
set_robust_list(0x7f4486a7fa20, 24) = 0
rt_sigaction(SIGRTMIN, {0x7f4485f627a0, [], SA_RESTORER|SA_SIGINFO, 0x7f4485f6b5e0}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {0x7f4485f62830, [], SA_RESTORER|SA_RESTART|SA_SIGINFO, 0x7f4485f6b5e0}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
brk(0) = 0xe9c000
brk(0xebd000) = 0xebd000
brk(0) = 0xebd000
socket(PF_LOCAL, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0) = 3
connect(3, {sa_family=AF_LOCAL, sun_path="/var/run/nscd/socket"}, 110) = 0
sendto(3, "\2\0\0\0\r\0\0\0\6\0\0\0hosts\0", 18, MSG_NOSIGNAL, NULL, 0) = 18
poll([{fd=3, events=POLLIN|POLLERR|POLLHUP}], 1, 5000) = 1 ([{fd=3, revents=POLLIN|POLLHUP}])
recvmsg(3, {msg_name(0)=NULL, msg_iov(2)=[{"hosts\0", 6}, {"Tt\313\0\0\0\0\0", 8}], msg_controllen=20, {cmsg_len=20, cmsg_level=SOL_SOCKET, cmsg_type=SCM_RIGHTS, {4}}, msg_flags=MSG_CMSG_CLOEXEC}, MSG_CMSG_CLOEXEC) = 14
mmap(NULL, 13333588, PROT_READ, MAP_SHARED, 4, 0) = 0x7f44852a4000
close(4) = 0
close(3) = 0
open("/etc/gai.conf", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
futex(0x7f44865413e0, FUTEX_WAKE_PRIVATE, 2147483647) = 0
socket(PF_NETLINK, SOCK_RAW, 0) = 3
bind(3, {sa_family=AF_NETLINK, pid=0, groups=00000000}, 12) = 0
getsockname(3, {sa_family=AF_NETLINK, pid=14727, groups=00000000}, [12]) = 0
sendto(3, "\24\0\0\0\26\0\1\3\276\245\201\\\0\0\0\0\0\0\0\0", 20, 0, {sa_family=AF_NETLINK, pid=0, groups=00000000}, 12) = 20
recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"L\0\0\0\24\0\2\0\276\245\201\\\2079\0\0\2\10\200\376\1\0\0\0\10\0\1\0\177\0\0\1"..., 4096}], msg_controllen=0, msg_flags=0}, 0) = 164
recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"\24\0\0\0\3\0\2\0\276\245\201\\\2079\0\0\0\0\0\0", 4096}], msg_controllen=0, msg_flags=0}, 0) = 20
close(3) = 0
socket(PF_INET, SOCK_DGRAM|SOCK_CLOEXEC, IPPROTO_IP) = 3
connect(3, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("172.217.5.238")}, 16) = 0
getsockname(3, {sa_family=AF_INET, sin_port=htons(56111), sin_addr=inet_addr("172.31.17.244")}, [16]) = 0
close(3) = 0
socket(PF_INET6, SOCK_DGRAM|SOCK_CLOEXEC, IPPROTO_IP) = 3
connect(3, {sa_family=AF_INET6, sin6_port=htons(80), inet_pton(AF_INET6, "2607:f8b0:4004:814::200e", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = -1 EADDRNOTAVAIL (Cannot assign requested address)
close(3) = 0
socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 3
fcntl(3, F_GETFL) = 0x2 (flags O_RDWR)
fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0
connect(3, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("172.217.5.238")}, 16) = -1 EINPROGRESS (Operation now in progress)
select(4, NULL, [3], NULL, NULL^CProcess 14727 detached
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