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SYSCALL(2)		      System Calls Manual		    SYSCALL(2)

NAME
       syscall,	__syscall -- indirect system call

LIBRARY
       Standard	C Library (libc, -lc)

SYNOPSIS
       #include	<sys/syscall.h>
       #include	<unistd.h>

       int
       syscall(int number, ...);

       off_t
       __syscall(quad_t	number,	...);

DESCRIPTION
       The syscall() function performs the system call whose assembly language
       interface  has the specified number with	the specified arguments.  Sym-
       bolic constants for system calls	 can  be  found	 in  the  header  file
       <sys/syscall.h>.	  The __syscall() form should be used when one or more
       of the arguments	is a 64-bit argument to	ensure that argument alignment
       is correct.  This system	call 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	 indi-
       cates an	error, and an error code is stored in errno.

HISTORY
       The syscall() function appeared in 4.0BSD.

BUGS
       There is	no way to simulate system calls	that have multiple return val-
       ues such	as pipe(2).

FreeBSD	13.2			 June 16, 1993			    SYSCALL(2)
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | HISTORY | BUGS

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