What is Readv?
The readv() function reads data from a file or a socket with descriptor fs and stores it in a set of buffers. The data is scattered into the buffers specified by iov[0]… iov[iovcnt-1]. Parameter Description fs. The file or socket descriptor.
What is Iov_base?
void *iov_base. Contains the address of a buffer. The readv function reads data from filedes and scatters it into the buffers described in vector , which is taken to be count structures long. As each buffer is filled, data is sent to the next. Note that readv is not guaranteed to fill all the buffers.
What is iovec?
The struct iovec defines one vector element. Normally, this structure is used as an array of multiple elements. For each transfer element, the pointer member iov_base points to a buffer that is receiving data for readv or is transmitting data for writev.
What is vectored read?
In computing, vectored I/O, also known as scatter/gather I/O, is a method of input and output by which a single procedure call sequentially reads data from multiple buffers and writes it to a single data stream, or reads data from a data stream and writes it to multiple buffers, as defined in a vector of buffers.
What is Writev in Linux?
The writev() system call writes iovcnt buffers of data described by iov to the file associated with the file descriptor fd (“gather output”). The writev() system call works just like write(2) except that multiple buffers are written out. Buffers are processed in array order.
What is scatter gather in mule?
Scatter-Gather is a routing message processor in Mule ESB runtime that sends a request message to multiple targets concurrently. It then collects the responses from all routes and aggregates them back into a single response. Unlike All, Scatter-Gather executes routes concurrently instead of sequentially.
What is Cache scope in Mule?
The Cache scope is for storing and reusing frequently called data. You can use a Cache scope to reduce the processing load on the Mule instance and to increase the speed of message processing within a flow. It is particularly effective for these tasks: Processing repeated requests for the same information.
What is VM queue in Mule?
Anypoint Connector for Virtual Machine (VM Connector) manages intra-app and inter-app communication through either transient or persistent asynchronous queues: When running a Mule application in single runtime instance mode, persistent queues work by serializing and storing the contents on the disk.
What do readv and writev ( 2 ) return?
The file referred to by fd must be capable of seeking. On success, readv () and preadv () return the number of bytes read; writev () and pwritev () return the number of bytes written. On error, -1 is returned, and errno is set appropriately. The errors are as given for read (2) and write (2).
How does writev ( ) work in sys.uio.h?
The pointer vector points to a struct iovec defined in as : Buffers are processed in the order specified. The readv () function works just like read (2) except that multiple buffers are filled. The writev () function works just like write (2) except that multiple buffers are written out.
What does writev ( ) do in Linux man?
The writev () system call writes iovcnt buffers of data described by iov to the file associated with the file descriptor fd (“gather output”). The pointer iov points to an array of iovec structures, defined in < sys/uio.h > as:
What does the writev ( ) function return on success?
On success, the readv () function returns the number of bytes read; the writev () function returns the number of bytes written. On error, -1 is returned, and errno is set appropriately. The errors are as given for read (2) and write (2). Additionally the following error is defined: The sum of the iov_len values overflows an ssize_t value.