某些极端场景下（比如CTF），或者绕过应用白名单限制，使用AWK来下载远程文件：
可利用的有：

/inet4/tcp/0/google.com/80
/inet/tcp/0/google.com/80
/inet/tcp/0/172.217.10.142/80
/inet/tcp/0/2899905166/80
/inet/tcp/000/\62\70\71\71\71\60\65\61\66\66/80/0080
/\i\156\e\164/\164\c\p/0000/\62\70\71\71\71\60\65\61\66\66/00080

demo：

awk 'BEGIN {
  RS = ORS = "\r\n"
  HTTPCon = "/inet4/tcp/0/google.com/80"
  print "HEAD / HTTP/1.1\r\nConnection: close\r\n"|& HTTPCon
  while ((HTTPCon |& getline) > 0)
     print $0
  close(HTTPCon)
}' 2>/dev/null

awk 'BEGIN {
  RS = ORS = "\r\n"
  HTTPCon = "/inet/tcp/0/2899905166/80"
  print "HEAD / HTTP/1.1\r\nConnection: close\r\n"|& HTTPCon
  while ((HTTPCon |& getline) > 0)
     print $0
  close(HTTPCon)
}' 2>/dev/null