c++ - linux bind don't create socket -

i having weird problem. trying create unix socket in directory not create 1 want. have cut down code below example.

#include <iostream> #include <string> #include <cstdlib> #include <string.h> #include <sys/un.h> #include <sys/socket.h> #include <errno.h> #include <limits.h>  int main(int argc, char *argv[]) {    std::string socketname(argv[1]);     socketname += "my_socket";      int  fd;     int  result;     struct  sockaddr_un addr;      fd = socket(af_unix, sock_stream, 0);      if (fd == -1)     {         std::cerr << "socket returned " << errno << ": " << strerror(errno) << std::endl;         exit(1);     }      memset(&addr, 0, sizeof(struct sockaddr_un));      addr.sun_family = af_unix;      strncpy(addr.sun_path, socketname.c_str(), sizeof(addr.sun_path) - 1);      result = bind(fd, (struct sockaddr *) &addr, sizeof(struct sockaddr_un));      if (result == -1)     {         std::cerr << "bind returned " << errno << ": " << strerror(errno ) << std::endl;         exit(1);     }      return 0; } 

the problem when run program like

./a.out /home/rasterblaster/local/media/video/television/unitedstates/series/californication/seasonone/xvid-conversions

i not "my_socket". instead find random socket named "xvid-convers".

/home/rasterblaster/local/media/video/television/unitedstates/series/californication/seasonone$ ls -la  drwxrwxrwx 3 rasterblaster rasterblaster  4096 2012-03-08 22:06 . drwxrwxrwx 3 rasterblaster rasterblaster  4096 2012-03-08 21:39 .. srwxrwxr-x 1 rasterblaster rasterblaster  0 2012-03-08 22:06:08 xvid-convers drwxrwxrwx 2 rasterblaster rasterblaster  4096 2012-03-08 21:39 xvid-conversions 

what doing wrong?

there nothing weird going on. if @ result of sizeof(addr.sun_path) should 100 or bytes. when try copy more size strncpy() truncating path fits sun_path , bind() creating filesystem entry name beyond last valid directory name.

there no benefit placing socket deep directory structure. can put in /tmp or /run or common directory clients , server have permission if want bit more security.

also, want

socketname += "/my_socket";  // prefix slash 

just in case path named passed doesn't end in slash.