1SOCKETCALL(2)              Linux Programmer's Manual             SOCKETCALL(2)
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NAME

6       socketcall - socket system calls
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SYNOPSIS

9       #include <linux/net.h>        /* Definition of SYS_* constants */
10       #include <sys/syscall.h>      /* Definition of SYS_socketcall */
11       #include <unistd.h>
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13       int syscall(SYS_socketcall, int call, unsigned long *args);
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15       Note: glibc provides no wrapper for socketcall(), necessitating the use
16       of syscall(2).
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DESCRIPTION

19       socketcall() is a common kernel  entry  point  for  the  socket  system
20       calls.   call  determines which socket function to invoke.  args points
21       to a block containing the actual arguments, which are passed through to
22       the appropriate call.
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24       User  programs  should  call  the  appropriate functions by their usual
25       names.  Only standard library implementors and kernel hackers  need  to
26       know about socketcall().
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28       call              Man page
29       SYS_SOCKET        socket(2)
30       SYS_BIND          bind(2)
31       SYS_CONNECT       connect(2)
32       SYS_LISTEN        listen(2)
33       SYS_ACCEPT        accept(2)
34       SYS_GETSOCKNAME   getsockname(2)
35       SYS_GETPEERNAME   getpeername(2)
36       SYS_SOCKETPAIR    socketpair(2)
37       SYS_SEND          send(2)
38       SYS_RECV          recv(2)
39       SYS_SENDTO        sendto(2)
40       SYS_RECVFROM      recvfrom(2)
41       SYS_SHUTDOWN      shutdown(2)
42       SYS_SETSOCKOPT    setsockopt(2)
43       SYS_GETSOCKOPT    getsockopt(2)
44       SYS_SENDMSG       sendmsg(2)
45       SYS_RECVMSG       recvmsg(2)
46       SYS_ACCEPT4       accept4(2)
47       SYS_RECVMMSG      recvmmsg(2)
48       SYS_SENDMMSG      sendmmsg(2)
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CONFORMING TO

51       This  call is specific to Linux, and should not be used in programs in‐
52       tended to be portable.
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NOTES

55       On some architectures—for example, x86-64 and ARM—there is  no  socket‐
56       call()  system  call;  instead socket(2), accept(2), bind(2), and so on
57       really are implemented as separate system calls.
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59       On x86-32, socketcall() was historically the only entry point  for  the
60       sockets  API.   However, starting in Linux 4.3, direct system calls are
61       provided on x86-32 for the sockets API.  This facilitates the  creation
62       of  seccomp(2)  filters that filter sockets system calls (for new user-
63       space binaries that are compiled to use the new entry points) and  also
64       provides a (very) small performance improvement.
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SEE ALSO

67       accept(2),  bind(2),  connect(2),  getpeername(2), getsockname(2), get‐
68       sockopt(2),  listen(2),  recv(2),  recvfrom(2),  recvmsg(2),   send(2),
69       sendmsg(2),  sendto(2),  setsockopt(2), shutdown(2), socket(2), socket‐
70       pair(2)
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COLOPHON

73       This page is part of release 5.13 of the Linux  man-pages  project.   A
74       description  of  the project, information about reporting bugs, and the
75       latest    version    of    this    page,    can     be     found     at
76       https://www.kernel.org/doc/man-pages/.
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80Linux                             2021-03-22                     SOCKETCALL(2)
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