C stdin, stderr, stdout C++ iostream Perl IO Python io Java C#

Size: px

Start display at page:

Download "C stdin, stderr, stdout C++ iostream Perl IO Python io Java C#"

Whitney Melton
7 years ago
Views:

2 Who uses them Definitions Idea originating in 1950 s Standard way to get Input and Output A source or sink of data C stdin, stderr, stdout C++ iostream Perl IO Python io Java C#

3 These are the people you can blame for the PHP streams implementation

4 We will write code (in pairs) There will be a quiz (with prizes) You get out what you put in participate! This is really 3 talks in one - Streams Filters Sockets

5 Abstracting I/O

6 Access input and output generically Can write and read linearly May or may not be seekable Comes in chunks of data

7 EVERYTHING include/require _once stream functions file system functions many other extensions

8 ALL IO Stream Contexts Stream Filter Stream Wrapper

9 Stream Resource that exhibits a flow or succession of data Wrapper Tells a stream how to handle specific protocols and encodings Context A set of parameters and options to tell a stream (or filter) how to behave

10 Scheme The name of the wrapper to be used. file, http, https, ftp, etc. Target Depends on the wrapper, filesystem uses a string path name, ssh2 uses a PHP resource home/bar/foo.txt file:///home/bar/foo.txt ftp://user:pass@ftp.example.com/foo.txt php://filter/read=string.toupper string.rot13/resource =

12 flock wrapper limitations non-existent pointers (infinite loops can and will happen) error handling

13 Parameters Options Modify or enhance a stream stream_context_set_param stream_context_set_option stream_context_create

15 Streams available by default

16 file:// ftp:// data:// glob://

17 SSL ftps:// ssl:// tls:// SSH ssh2.shell:// ssh2.exec:// ssh2.tunnel:// ssh2.sftp:// ssh2.scp:// Phar phar:// Zlib compress.zlib:// zlib:// Bzip compress.bz2://

21 Pipes STDIN, STDOUT, STDERR proc_open popen

22 php://stdin php://stdout php://stderr php://output php://input php://filter (5.0.0) php://memory (5.1.0) php://temp (5.1.0)

24 1. Get a Feed from Flickr No curl installed, allow_url_fopen is on 3. Display however you would like

25 Grab the feed as xml, pop it through simplexml, loop and display the output to a webpage

27 Userland Filters and Streams

28 There are no interfaces Implement as though there were an interface Seekable is optional Flushable is optional Directory support is optional

29 Code Information fopen file_get_contents Return true or false $this->context will have any context metadata

30 Code Information fread fgets file_get_contents etc Return string data or false $this->context will have any context metadata

31 Code Information fwrite file_put_contents get in a string of data to deal with return how many bytes you wrote

32 Code Information feof file_get_contents fread etc Return true or false $this->context will have any context metadata

33 Code Information fclose file_get_contents Don t return anything any cleanup should go here

34 fstat calls stream_stat EVERYTHING ELSE uses url_stat Good idea to do both Return an array of data identical to stat()

35 stream_seek stream_tell stream_flush

36 mkdir rmdir dir_closedir dir_opendir dir_readdir dir_rewinddir

37 stream_lock stream_cast rename unlink

38 Create a custom wrapper for any kind of network or shared memory storage you want (except s3 which is way overdone) Implement at least the basics extra points for more features

39 Wrapper for wincache (btw, porting this to apc would be a breeze) Does basics + seek + flush (since we re caching) + rename + unlink No directories

40 Use Case land when streams make sense

41 Data in s3 Data locally during development Easy switch out if alternative storage is ever desired Storing image files

42 Existing Zend Framework Code Register the s3:// wrapper Use a configuration setting for the stream to use for all images on the system

43 Store and edit template files in a database Have the snappiness of including from disk Minimal Configuration

44 db:// stream simple stream wrapper that looks for the template in the db, and writes it to the filesystem before returning the data The cached location is FIRST in the include path, so if it fails, the db stream gets hit

45 Talk to mercurial (hg binary) hg communicates via command line continue to pipe additional commands

46 Use proc_open to keep a pipe to the binary going Pass commands through stdin pipe as necessary Abstract this out to other binaries that are used by the system

47 1. Name 3 Built in PHP streams. 2. What is a Context? A Wrapper? A Stream? 3. How do you identify a stream? 4. Name two extensions that provide additional PHP streams.

48 simplifying-file-operations-using-phpstream-wrappers

50 Because everyone needs to rot13 a file they open on the fly

51 Performs operations on stream data Can be prepended or appended (even on the fly) Can be attached to read or write When a filter is added for read and write, two instances of the filter are created.

53 Data has an input and output state When reading in chunks, you may need to cache in between reads to make filters useful Use the right tool for the job

54 string filters string.rot13 string.toupper string.tolower string.strip_tags

55 convert filters convert.* base64-encode base64-decode quoted-printable-encode quoted-printable-decode dechunk decode remote HTTP chunked encoding streams consumed eats data (that s all it does)

56 bzip.compress and bzip.compress convert.iconv.* zlib.inflate and zlib.deflate mcrypt.* and mdecrypt.*

57 Extend an internal class php_user_filter It s not abstract Yes that s a horrible name Remember this pre-dates php 5.0 decisions

58 Code Information oncreate basically a constructor Called every time PHP needs a new filter (on every stream) return true or false

59 php_user_filter $this->filtername $this->params $this->stream

60 Code Information onclose basically a destructor no return

61 Code Information MUST return PSFS_PASS_ON PSFS_FEED_ME PSFS_ERR_FATAL You get buckets of data and do stuff to them

63 $in and $out are bucket brigades containing opaque buckets of data You can only touch buckets and brigades with the stream_bucket_* functions You get a bucket using stream_bucket_make_writeable

64 Given a list of bad words (we ll use the 7 bad words), write a filter to remove them from text Given a commonly misspelled word, fix the spelling in the text

65 I only did the bad words one, and created an extremely naïve regex that stripped the bad words from whatever text it finds. It buffers the entirety of the text before doing the replacement this could be done by looking for word boundaries and doing it piecemeal to improve performance

67 1. What term is used to describe data handling in filters? 2. Name two built in filters you should be using and why. 3. What is the default mode filters are appended with? 4. What is the difference between appending and prepending a filter?

69 Putter about the network with me

70 Socket Bidirectional network stream that speaks a protocol Transport Tells a network stream how to communicate Wrapper Tells a stream how to handle specific protocols and encodings

71 Network Stream, Network Transport, Socket Transport Slightly different behavior from a file stream Bi-directional data

72 Sockets block stream_set_blocking stream_set_timeout stream_select feof means connection_closed? huge reads or writes (think 8K) stream_get_meta_data is READ ONLY

73 New APIS in streams and filesystem functions are replacements Extension is old and not really kept up to date (bit rot) Extension is more low level stream_socket_server stream_socket_client

75 tcp udp unix udg SSL extension ssl sslv2 sslv3 tls

76 Given two files of quotes, write a server with PHP streams methods to return random quotes, optionally allow client to pick which file to retrieve quotes from Given a simple tcp server that will return a random quote make a client that pulls quotes for users

77 socket_server.php uses stream_socket_server and stream_accept socket_client.php uses stream_socket_client and a bit of loop magic to make a little cli app

78 1. How is a socket different from a stream? 2. What transports does PHP provide by default? 3. Name the two most commonly used stream socket functions. 4. How can a user add additional transports to PHP?

79 ocket

80 Set of interfaces for streams Improved based filter class Wrappers for chmod and touch More tests! Any you have?

81 IRC freenode auroraeosrose #php-gtk #coapp

$ftp = Net::FTP->new("some.host.name", Debug => 0) or die "Cannot connect to some.host.name: $@";

$ftp = Net::FTP->new(some.host.name, Debug => 0) or die Cannot connect to some.host.name: $@; NAME Net::FTP - FTP Client class SYNOPSIS use Net::FTP; $ftp = Net::FTP->new("some.host.name", Debug => 0) or die "Cannot connect to some.host.name: $@"; $ftp->login("anonymous",'-anonymous@') or die "Cannot