READ(2)             UNIX Programmer's Manual              READ(2)

NAME
     read - read from file

SYNOPSIS
     read(fildes, buffer, nbytes)
     char *buffer;
     unsigned nbytes;

DESCRIPTION
     A file descriptor is a word returned from a successful _o_p_e_n,
     _c_r_e_a_t, _d_u_p, or _p_i_p_e(2) call.  _B_u_f_f_e_r is the location of
     _n_b_y_t_e_s contiguous bytes into which the input will be placed.
     It is not guaranteed that all _n_b_y_t_e_s bytes will be read; for
     example if the file refers to a typewriter at most one line
     will be returned.  In any event the number of characters
     read is returned.

     If the returned value is 0, then end-of-file has been
     reached.

ERRORS
     _R_e_a_d will fail if one or more of the following is true:

     [EBADF]             _F_i_l_d_e_s is not a valid file descriptor
                         open for reading.

     [EFAULT]            _B_u_f points outside the process's allo-
                         cated address space.

     [EINTR]             A read from a slow device was inter-
                         rupted (before any data arrived) by the
                         delivery of a signal.

SEE ALSO
     creat(2), dup(2), open(2), pipe(2)

ASSEMBLER
     (read = 3.)
     (file descriptor in r0)
     sys read; buffer; nbytes
     (byte count in r0)

Printed 5/22/83                                                 1