socketcall(2) System Calls Manual socketcall(2)
NAME
socketcall - socket system calls
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <linux/net.h> /* Definition of SYS_* constants */
#include <sys/syscall.h> /* Definition of SYS_socketcall */
#include <unistd.h>
int syscall(SYS_socketcall, int call, unsigned long *args);
Note: glibc provides no wrapper for socketcall(), necessitating the use
of syscall(2).
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 appro-
priate call.
User programs should call the appropriate functions by their usual
names. Only standard library implementors and kernel hackers need to
know about socketcall().
call Man page
SYS_SOCKET socket(2)
SYS_BIND bind(2)
SYS_CONNECT connect(2)
SYS_LISTEN listen(2)
SYS_ACCEPT accept(2)
SYS_GETSOCKNAME getsockname(2)
SYS_GETPEERNAME getpeername(2)
SYS_SOCKETPAIR socketpair(2)
SYS_SEND send(2)
SYS_RECV recv(2)
SYS_SENDTO sendto(2)
SYS_RECVFROM recvfrom(2)
SYS_SHUTDOWN shutdown(2)
SYS_SETSOCKOPT setsockopt(2)
SYS_GETSOCKOPT getsockopt(2)
SYS_SENDMSG sendmsg(2)
SYS_RECVMSG recvmsg(2)
SYS_ACCEPT4 accept4(2)
SYS_RECVMMSG recvmmsg(2)
SYS_SENDMMSG sendmmsg(2)
VERSIONS
On some architectures—for example, x86-64 and ARM—there is no socket-
call() system call; instead socket(2), accept(2), bind(2), and so on re-
ally are implemented as separate system calls.
STANDARDS
Linux.
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), getsock-
opt(2), listen(2), recv(2), recvfrom(2), recvmsg(2), send(2),
sendmsg(2), sendto(2), setsockopt(2), shutdown(2), socket(2), socket-
pair(2)
Linux man-pages 6.9.1 2024-05-02 socketcall(2)
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