socketcall(2)

NAME

   socketcall - socket system calls

SYNOPSIS

   int socketcall(int call, unsigned long *args);

DESCRIPTION

   socketcall()  is  a  common  kernel  entry  point for the socket system
   calls.  call determines which socket function to invoke.   args  points
   to a block containing the actual arguments, which are passed through to
   the appropriate call.

   User programs should call the  appropriate  functions  by  their  usual
   names.   Only  standard library implementors and kernel hackers need to
   know about socketcall().

CONFORMING TO

   This call is specific to Linux, and should  not  be  used  in  programs
   intended to be portable.

NOTES

   On  a  some  architectures---for  example,  x86-64  and  ARM---there  is no
   socketcall() system call; instead socket(2), accept(2), bind(2), and so
   on really are implemented as separate system calls.

   On  x86-32,  socketcall() was historically the only entry point for the
   sockets API.  However, starting in Linux 4.3, direct system  calls  are
   provided  on x86-32 for the sockets API.  This facilitates the creation
   of seccomp(2) filters that filter sockets system calls (for  new  user-
   space  binaries that are compiled to use the new entry points) and also
   provides a (very) small performance improvement.

SEE ALSO

   accept(2),   bind(2),   connect(2),   getpeername(2),   getsockname(2),
   getsockopt(2),  listen(2),  recv(2),  recvfrom(2), recvmsg(2), send(2),
   sendmsg(2),   sendto(2),   setsockopt(2),    shutdown(2),    socket(2),
   socketpair(2)

COLOPHON

   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at
   https://www.kernel.org/doc/man-pages/.

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