man2/socketcall.2

   1 .\" Copyright (c) 1995 Michael Chastain (mec@shell.portal.com), 15 April 1995.
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  24 .\" Modified Tue Oct 22 22:11:53 1996 by Eric S. Raymond <esr@thyrsus.com>
  25 .TH SOCKETCALL 2 2017-09-15 "Linux" "Linux Programmer's Manual"
  26 .SH NAME
  27 socketcall \- socket system calls
  28 .SH SYNOPSIS
  29 .B #include <linux/net.h>
  30 .PP
  31 .BI "int socketcall(int " call ", unsigned long *" args );
  32 .SH DESCRIPTION
  33 .BR socketcall ()
  34 is a common kernel entry point for the socket system calls.
  35 .I call
  36 determines which socket function to invoke.
  37 .I args
  38 points to a block containing the actual arguments,
  39 which are passed through to the appropriate call.
  40 .PP
  41 User programs should call the appropriate functions by their usual names.
  42 Only standard library implementors and kernel hackers need to know about
  43 .BR socketcall ().
  44 .PP
  45 .TS
  46 tab(:);
  47 l l.
  48 \fIcall\fR:Man page
  49 T{
  50 .B SYS_SOCKET
  51 T}:T{
  52 .BR socket (2)
  53 T}
  54 T{
  55 .B SYS_BIND
  56 T}:T{
  57 .BR bind (2)
  58 T}
  59 T{
  60 .B SYS_CONNECT
  61 T}:T{
  62 .BR connect (2)
  63 T}
  64 T{
  65 .B SYS_LISTEN
  66 T}:T{
  67 .BR listen (2)
  68 T}
  69 T{
  70 .B SYS_ACCEPT
  71 T}:T{
  72 .BR accept (2)
  73 T}
  74 T{
  75 .B SYS_GETSOCKNAME
  76 T}:T{
  77 .BR getsockname (2)
  78 T}
  79 T{
  80 .B SYS_GETPEERNAME
  81 T}:T{
  82 .BR getpeername (2)
  83 T}
  84 T{
  85 .B SYS_SOCKETPAIR
  86 T}:T{
  87 .BR socketpair (2)
  88 T}
  89 T{
  90 .B SYS_SEND
  91 T}:T{
  92 .BR send (2)
  93 T}
  94 T{
  95 .B SYS_RECV
  96 T}:T{
  97 .BR recv (2)
  98 T}
  99 T{
 100 .B SYS_SENDTO
 101 T}:T{
 102 .BR sendto (2)
 103 T}
 104 T{
 105 .B SYS_RECVFROM
 106 T}:T{
 107 .BR recvfrom (2)
 108 T}
 109 T{
 110 .B SYS_SHUTDOWN
 111 T}:T{
 112 .BR shutdown (2)
 113 T}
 114 T{
 115 .B SYS_SETSOCKOPT
 116 T}:T{
 117 .BR setsockopt (2)
 118 T}
 119 T{
 120 .B SYS_GETSOCKOPT
 121 T}:T{
 122 .BR getsockopt (2)
 123 T}
 124 T{
 125 .B SYS_SENDMSG
 126 T}:T{
 127 .BR sendmsg (2)
 128 T}
 129 T{
 130 .B SYS_RECVMSG
 131 T}:T{
 132 .BR recvmsg (2)
 133 T}
 134 T{
 135 .B SYS_ACCEPT4
 136 T}:T{
 137 .BR accept4 (2)
 138 T}
 139 T{
 140 .B SYS_RECVMMSG
 141 T}:T{
 142 .BR recvmmsg (2)
 143 T}
 144 T{
 145 .B SYS_SENDMMSG
 146 T}:T{
 147 .BR sendmmsg (2)
 148 T}
 149 .TE
 150 .SH CONFORMING TO
 151 This call is specific to Linux, and should not be used in programs
 152 intended to be portable.
 153 .SH NOTES
 154 On a some architectures\(emfor example, x86-64 and ARM\(emthere is no
 155 .BR socketcall ()
 156 system call; instead
 157 .BR socket (2),
 158 .BR accept (2),
 159 .BR bind (2),
 160 and so on really are implemented as separate system calls.
 161 .PP
 162 On x86-32,
 163 .BR socketcall ()
 164 was historically the only entry point for the sockets API.
 165 However, starting in Linux 4.3,
 166 .\" commit 9dea5dc921b5f4045a18c63eb92e84dc274d17eb
 167 direct system calls are provided on x86-32 for the sockets API.
 168 This facilitates the creation of
 169 .BR seccomp (2)
 170 filters that filter sockets system calls
 171 (for new user-space binaries that are compiled
 172 to use the new entry points)
 173 and also provides a (very) small performance improvement.
 174 .SH SEE ALSO
 175 .BR accept (2),
 176 .BR bind (2),
 177 .BR connect (2),
 178 .BR getpeername (2),
 179 .BR getsockname (2),
 180 .BR getsockopt (2),
 181 .BR listen (2),
 182 .BR recv (2),
 183 .BR recvfrom (2),
 184 .BR recvmsg (2),
 185 .BR send (2),
 186 .BR sendmsg (2),
 187 .BR sendto (2),
 188 .BR setsockopt (2),
 189 .BR shutdown (2),
 190 .BR socket (2),
 191 .BR socketpair (2)