IN: io.monitors
USING: help.markup help.syntax continuations ;

HELP: <monitor>
{ $values { "path" "a pathname string" } { "recursive?" "a boolean" } { "monitor" "a new monitor" } }
{ $description "Opens a file system change monitor which listens for changes on " { $snippet "path" } ". The boolean indicates whether changes in subdirectories should be reported."
$nl
"Not all operating systems support recursive monitors; if recursive monitoring is not available, an error is thrown and the caller must implement alternative logic for monitoring subdirectories." } ;

HELP: next-change
{ $values { "monitor" "a monitor" } { "path" "a pathname string" } { "changed" "a change descriptor" } }
{ $description "Waits for file system changes and outputs the pathname of the first changed file. The change descriptor is aq sequence of symbols documented in " { $link "io.monitors.descriptors" } "." } ;

HELP: with-monitor
{ $values { "path" "a pathname string" } { "recursive?" "a boolean" } { "quot" "a quotation with stack effect " { $snippet "( monitor -- )" } } }
{ $description "Opens a file system change monitor and passes it to the quotation. Closes the monitor after the quotation returns or throws an error." } ;

HELP: +add-file+
{ $description "Indicates that the file has been added to the directory." } ;

HELP: +remove-file+
{ $description "Indicates that the file has been removed from the directory." } ;

HELP: +modify-file+
{ $description "Indicates that the file contents have changed." } ;

HELP: +rename-file+
{ $description "Indicates that file has been renamed." } ;

ARTICLE: "io.monitors.descriptors" "File system change descriptors"
"Change descriptors output by " { $link next-change } ":"
{ $subsection +add-file+ }
{ $subsection +remove-file+ }
{ $subsection +modify-file+ }
{ $subsection +rename-file+ }
{ $subsection +add-file+ } ;

ARTICLE: "io.monitors" "File system change monitors"
"File system change monitors listen for changes to file names, attributes and contents under a specified directory. They can optionally be recursive, in which case subdirectories are also monitored."
$nl
"Creating a file system change monitor and listening for changes:"
{ $subsection <monitor> }
{ $subsection next-change }
{ $subsection "io.monitors.descriptors" }
"Monitors are closed by calling " { $link dispose } " or " { $link with-disposal } "."
$nl
"A utility combinator which opens a monitor and cleans it up after:"
{ $subsection with-monitor }
"An example which watches the Factor directory for changes:"
{ $code
    "USE: io.monitors"
    ": watch-loop ( monitor -- )"
    "    dup next-change . . nl nl flush watch-loop ;"
    ""
    "\"\" resource-path f [ watch-loop ] with-monitor"
} ;

ABOUT: "io.monitors"