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syscall(2) [osx man page]

SYSCALL(2)						      BSD System Calls Manual							SYSCALL(2)

NAME
syscall -- indirect system call SYNOPSIS
#include <sys/syscall.h> #include <unistd.h> int syscall(int number, ...); DESCRIPTION
Syscall() performs the system call whose assembly language interface has the specified number with the specified arguments. Symbolic con- stants for system calls can be found in the header file <sys/syscall.h>. This function is useful for testing new system calls that do not have entries in the C library. RETURN VALUES
The return values are defined by the system call being invoked. In general, a 0 return value indicates success. A -1 return value indicates an error, and an error code is stored in errno. BUGS
There is no way to simulate system calls that have multiple return values such as pipe(2). HISTORY
The syscall() function call appeared in 4.0BSD. 4th Berkeley Distribution June 23, 2008 4th Berkeley Distribution

Check Out this Related Man Page

SYSCALL(2)						     Linux Programmer's Manual							SYSCALL(2)

NAME
syscall - indirect system call SYNOPSIS
#define _GNU_SOURCE /* or _BSD_SOURCE or _SVID_SOURCE */ #include <unistd.h> #include <sys/syscall.h> /* For SYS_xxx definitions */ int syscall(int number, ...); DESCRIPTION
syscall() performs the system call whose assembly language interface has the specified number with the specified arguments. Symbolic con- stants for system calls can be found in the header file <sys/syscall.h>. RETURN VALUE
The return value is defined by the system call being invoked. In general, a 0 return value indicates success. A -1 return value indicates an error, and an error code is stored in errno. NOTES
syscall() first appeared in 4BSD. EXAMPLE
#define _GNU_SOURCE #include <unistd.h> #include <sys/syscall.h> #include <sys/types.h> int main(int argc, char *argv[]) { pid_t tid; tid = syscall(SYS_gettid); } SEE ALSO
_syscall(2), intro(2), syscalls(2) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2007-07-26 SYSCALL(2)
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