vrb_data_ptr(3) [debian man page]

vrb_data_ptr(3) 					      VRB Programmer's Manual						   vrb_data_ptr(3)

NAME

       vrb_data_ptr - return pointer to data

LIBRARY

       -lvrb

SYNOPSIS

       #include <vrb.h>

       size_t vrb_data_ptr(vrb_p vrb);

DESCRIPTION

       vrb_data_ptr  returns the pointer to the beginning of the contiguous block of data within the virtual ring buffer.  The pointer has meaning
       only if there is data in the buffer.  If there is no data in the buffer, an arbitrary pointer is  returned  and	must  not  be  used.   Use
       vrb_data_len(3) or vrb_is_empty(3) to determine if vrb_data_ptr(3) has a meaningful pointer.

       The caller may access all of this data, and should call vrb_take(3) to indicate how much data has been removed from the buffer.

ARGUMENTS

       vrb_p vrb
       specifies  the  virtual	ring buffer to obtain the data pointer from.  If a NULL or invalid pointer is given, results are unpredictable and
       are likely to be disasterous.

RETURN VALUE

       size_t
       The pointer to the data in the virtual ring buffer is returned.

SEE ALSO

       vrb(3),	vrb_capacity(3),  vrb_data_len(3),  vrb_destroy(3),  vrb_get(3),  vrb_get_min(3),   vrb_give(3),   vrb_init(3),   vrb_init_opt(3),
       vrb_is_empty(3),   vrb_is_full(3),   vrb_is_not_empty(3),   vrb_is_not_full(3),	 vrb_move(3),	vrb_new(3),   vrb_new_opt(3),  vrb_put(3),
       vrb_put_all(3), vrb_read(3), vrb_read_min(3), vrb_resize(3), vrb_space_len(3), vrb_space_ptr(3), vrb_take(3), vrb_uninit(3),  vrb_write(3),
       vrb_write_min(3)

vrb								    2002-09-30							   vrb_data_ptr(3)

vrb_read_min(3) 					      VRB Programmer's Manual						   vrb_read_min(3)

NAME

       vrb_read_min - read a minimum of data into a VRB

LIBRARY

       -lvrb

SYNOPSIS

       #include <vrb.h>

       size_t vrb_read_min(vrb_p vrb, int fd, size_t maxsize, size_t minsize);

DESCRIPTION

       vrb_read_min  reads  a  minimum	amount	of data from a specified open file descriptor using read(2) into the specified virtual ring buffer
       until the specified maximum length has been read, the buffer is full, or end-of-file, or an error is returned (including EAGAIN or  EWOULD-
       BLOCK  for  a  non-blocking descriptor).  If there is insufficient space in the buffer to read the minimum amount, then read(2) will not be
       called.

ARGUMENTS

       vrb_p vrb
       specifies which virtual ring buffer.

       int fd
       specifies the open file descriptor to read from

       size_t maxsize
       specifies the maximum length to read, or ~0 for unlimited.

       size_t minsize
       specifies the minimum length to read.

RETURN VALUE

       size_t
       If successful, the actual length of data read into the buffer is returned.  If the minimum amount of space was not available to read  into,
       0  is returned.	If end-of-file occurs, the return value is ~0 and errno is 0.  If an error occurs from read(2), the return value is ~0 and
       errno is set by read(2).

ERRORS

       If an error is returned, then errno will have one of the following values:

       0      An end-of-file has occurred.  Note that this is a different way of returning an end-of-file condition than read(2) uses.

       EINVAL An invalid virtual ring buffer pointer was specified.

SEE ALSO

       vrb(3),	vrb_capacity(3),  vrb_data_len(3),  vrb_data_ptr(3),  vrb_destroy(3),  vrb_get(3),   vrb_get_min(3),   vrb_give(3),   vrb_init(3),
       vrb_init_opt(3),   vrb_is_empty(3),  vrb_is_full(3),  vrb_is_not_empty(3),  vrb_is_not_full(3),	vrb_move(3),  vrb_new(3),  vrb_new_opt(3),
       vrb_put(3), vrb_put_all(3), vrb_read(3),  vrb_resize(3),  vrb_space_len(3),  vrb_space_ptr(3),  vrb_take(3),  vrb_uninit(3),  vrb_write(3),
       vrb_write_min(3), read(2)

vrb								    2002-09-30							   vrb_read_min(3)