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

     syscall -- indirect system call

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

     syscall(int number, ...);

     Syscall() performs the system call whose assembly language interface has the specified number with the
     specified arguments.  Symbolic constants 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.

     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.

     There is no way to simulate system calls that have multiple return values such as pipe(2).

     The syscall() function call appeared in 4.0BSD.

4th Berkeley Distribution        June 23, 2008       4th Berkeley Distribution

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