inotifytools library public interface. More...

Functions
void	inotifytools_cleanup ()
int	inotifytools_error ()
char *	inotifytools_event_to_str (int events)
char *	inotifytools_event_to_str_sep (int events, char sep)
char *	inotifytools_filename_from_wd (int wd)
int	inotifytools_fprintf (FILE file, struct inotify_event event, char *fmt)
int	inotifytools_get_max_queued_events ()
int	inotifytools_get_max_user_instances ()
int	inotifytools_get_max_user_watches ()
int	inotifytools_get_num_watches ()
int	inotifytools_get_stat_by_filename (char const *filename, int event)
int	inotifytools_get_stat_by_wd (int wd, int event)
int	inotifytools_get_stat_total (int event)
int	inotifytools_ignore_events_by_regex (char const *pattern, int flags)
int	inotifytools_initialize ()
void	inotifytools_initialize_stats ()
struct inotify_event *	inotifytools_next_event (int timeout)
struct inotify_event *	inotifytools_next_events (int timeout, int num_events)
int	inotifytools_printf (struct inotify_event event, char fmt)
int	inotifytools_remove_watch_by_filename (char const *filename)
int	inotifytools_remove_watch_by_wd (int wd)
void	inotifytools_replace_filename (char const oldname, char const newname)
void	inotifytools_set_filename_by_filename (char const oldname, char const newname)
void	inotifytools_set_filename_by_wd (int wd, char const *filename)
void	inotifytools_set_printf_timefmt (char *fmt)
int	inotifytools_snprintf (char out, int size, struct inotify_event event, char *fmt)
int	inotifytools_sprintf (char out, struct inotify_event event, char *fmt)
int	inotifytools_str_to_event (char const *event)
int	inotifytools_str_to_event_sep (char const *event, char sep)
int	inotifytools_watch_file (char const *filename, int events)
int	inotifytools_watch_files (char const *filenames[], int events)
int	inotifytools_watch_recursively (char const *path, int events)
int	inotifytools_watch_recursively_with_exclude (char const path, int events, char const *exclude_list)
int	inotifytools_wd_from_filename (char const *filename)

Detailed Description

inotifytools library public interface.

Author:: Rohan McGovern, <rohan.nosp@m.@mcg.nosp@m.overn.nosp@m..id..nosp@m.au>

This library provides a thin layer on top of the basic inotify interface. The primary use is to easily set up watches on files, potentially many files at once, and read events without having to deal with low-level I/O. There are also several utility functions for inotify-related string formatting.

To use this library, you must #include the following headers accordingly:

<inotifytools/inotifytools.h> - to use any functions declared in this file.
<inotifytools/inotify.h> - to have the inotify_event type defined and the numeric IN_* event constants defined. If <sys/inotify.h> was present on your system at compile time, this header simply includes that. Otherwise it includes <inotifytools/inotify-nosys.h>.

Example

This very simple program recursively watches the entire directory tree under its working directory for events, then prints them out with a timestamp.

#include <stdio.h>
#include <string.h>
#include <inotifytools/inotifytools.h>
#include <inotifytools/inotify.h>
/*
 * libinotifytools example program.
 * Compile with gcc -linotifytools example.c
 */
int main() {
        // initialize and watch the entire directory tree from the current working
        // directory downwards for all events
        if ( !inotifytools_initialize()
          || !inotifytools_watch_recursively( ".", IN_ALL_EVENTS ) ) {
                fprintf(stderr, "%s\n", strerror( inotifytools_error() ) );
                return -1;
        }
        // set time format to 24 hour time, HH:MM:SS
        inotifytools_set_printf_timefmt( "%T" );
        // Output all events as "<timestamp> <path> <events>"
        struct inotify_event * event = inotifytools_next_event( -1 );
        while ( event ) {
                inotifytools_printf( event, "%T %w%f %e\n" );
                event = inotifytools_next_event( -1 );
        }
}

Events

Note:: This section comes almost verbatim from the inotify(7) man page.

Warning:: The information here applies to inotify in Linux 2.6.17. Older versions of Linux may not support all the events described here.

The following numeric events can be specified to functions in inotifytools, and may be present in events returned through inotifytools:

IN_ACCESS - File was accessed (read) *
IN_ATTRIB - Metadata changed (permissions, timestamps, extended attributes, etc.) *
IN_CLOSE_WRITE - File opened for writing was closed *
IN_CLOSE_NOWRITE - File not opened for writing was closed *
IN_CREATE - File/directory created in watched directory *
IN_DELETE - File/directory deleted from watched directory *
IN_DELETE_SELF - Watched file/directory was itself deleted
IN_MODIFY - File was modified *
IN_MOVE_SELF - Watched file/directory was itself moved
IN_MOVED_FROM - File moved out of watched directory *
IN_MOVED_TO - File moved into watched directory *
IN_OPEN - File was opened *

When monitoring a directory, the events marked with an asterisk * above can occur for files in the directory, in which case the name field in the returned inotify_event structure identifies the name of the file within the directory.

The IN_ALL_EVENTS macro is defined as a bit mask of all of the above events.

Two additional convenience macros are IN_MOVE, which equates to IN_MOVED_FROM|IN_MOVED_TO, and IN_CLOSE which equates to IN_CLOSE_WRITE|IN_CLOSE_NOWRITE.

The following bitmasks can also be provided when creating a new watch:

IN_DONT_FOLLOW - Don't dereference pathname if it is a symbolic link
IN_MASK_ADD - Add (OR) events to watch mask for this pathname if it already exists (instead of replacing mask)
IN_ONESHOT - Monitor pathname for one event, then remove from watch list
IN_ONLYDIR - Only watch pathname if it is a directory

The following bitmasks may occur in events generated by a watch:

IN_IGNORED - Watch was removed explicitly (inotifytools_remove_watch_*) or automatically (file was deleted, or file system was unmounted)
IN_ISDIR - Subject of this event is a directory
IN_Q_OVERFLOW - Event queue overflowed (wd is -1 for this event)
IN_UNMOUNT - File system containing watched object was unmounted

TODO list

Todo:: Improve wd/filename mapping. Currently there is no explicit code for handling different filenames mapping to the same inode (and hence, wd). gamin's approach sounds good: let the user watch an inode using several different filenames, and when an event occurs on the inode, generate an event for each filename.

Definition in file inotifytools.h.

Function Documentation

void inotifytools_cleanup ( )

Close inotify and free the memory used by inotifytools.

If you call this function, you must call inotifytools_initialize() again before any other functions can be used.

Definition at line 326 of file inotifytools.c.

References inotifytools_cleanup().

Referenced by inotifytools_cleanup().

int inotifytools_error ( )

Get the last error which occurred.

When a function fails, call this to find out why. The returned value is a typical errno value, the meaning of which depends on context. For example, if inotifytools_watch_file() fails because you attempt to watch a file which doesn't exist, this function will return ENOENT.

Returns:: an error code.

Definition at line 1590 of file inotifytools.c.

References inotifytools_error().

Referenced by inotifytools_error().

char* inotifytools_event_to_str ( int events )

Convert event from integer form to string form (as in inotify.h).

The returned string is from static storage; subsequent calls to this function or inotifytools_event_to_str_sep() will overwrite it. Don't free() it and make a copy if you want to keep it.

Parameters:

events OR'd event(s) in integer form as defined in inotify.h. See section Events.

Returns:: comma-separated string representing the event(s), in no particular order

Example

   int eventnum == IN_MODIFY | IN_CLOSE | IN_CREATE;
   char * eventstr = inotifytools_event_to_str( eventnum );
   printf( "%s\n", eventstr );
   // outputs something like MODIFY,CLOSE,CREATE but order not guaranteed.

Definition at line 628 of file inotifytools.c.

References inotifytools_event_to_str(), and inotifytools_event_to_str_sep().

Referenced by inotifytools_event_to_str(), and inotifytools_snprintf().

char* inotifytools_event_to_str_sep	(	int	events,
		char	sep
	)

Convert event from integer form to string form (as in inotify.h).

The returned string is from static storage; subsequent calls to this function or inotifytools_event_to_str() will overwrite it. Don't free() it and make a copy if you want to keep it.

Parameters:

events	OR'd event(s) in integer form as defined in inotify.h
sep	character used to separate events

Returns:: sep separated string representing the event(s), in no particular order. If the integer is not made of OR'ed inotify events, the string returned will be a hexadecimal representation of the integer.

Example

   int eventnum == IN_MODIFY | IN_CLOSE | IN_CREATE;
   char * eventstr = inotifytools_event_to_str_sep( eventnum, '-' );
   printf( "%s\n", eventstr );
   // outputs something like MODIFY-CLOSE-CREATE but order not guaranteed.

Definition at line 656 of file inotifytools.c.

References inotifytools_event_to_str_sep().

Referenced by inotifytools_event_to_str(), inotifytools_event_to_str_sep(), and inotifytools_snprintf().

char* inotifytools_filename_from_wd ( int wd )

Get the filename used to establish a watch.

inotifytools_initialize() must be called before this function can be used.

Parameters:

wd	watch descriptor.

Returns:: filename associated with watch descriptor wd, or NULL if wd is not associated with any filename.

Note:: This always returns the filename which was used to establish a watch. This means the filename may be a relative path. If this isn't desired, then always use absolute paths when watching files. Also, this is not necessarily the filename which might have been used to cause an event on the file, since inotify is inode based and there can be many filenames mapping to a single inode. Finally, if a file is moved or renamed while being watched, the filename returned will still be the original name.

Definition at line 763 of file inotifytools.c.

References inotifytools_filename_from_wd().

Referenced by inotifytools_filename_from_wd(), and inotifytools_snprintf().

int inotifytools_fprintf	(	FILE *	file,
		struct inotify_event *	event,
		char *	fmt
	)

Print a string to a file using an inotify_event and a printf-like syntax. The string written will only ever be up to 4096 characters in length.

Parameters:

file	file to print to
event	the event to use to construct a string.
fmt	the format string used to construct a string.

Returns:: number of characters written, or -1 if an error occurs.

Format string syntax

The following tokens will be replaced with the specified string:

%w - This will be replaced with the name of the Watched file on which an event occurred.
%f - When an event occurs within a directory, this will be replaced with the name of the File which caused the event to occur. Otherwise, this will be replaced with an empty string.
%e - Replaced with the Event(s) which occurred, comma-separated.
%Xe - Replaced with the Event(s) which occurred, separated by whichever character is in the place of `X'.
%T - Replaced by the current Time in the format specified by the string previously passed to inotifytools_set_printf_timefmt(), or replaced with an empty string if that function has never been called.

Example

   // suppose this is the only file watched.
   inotifytools_watch_file( "mydir/", IN_CLOSE );
  
   // wait until an event occurs
   struct inotify_event * event = inotifytools_next_event( -1 );
  
   inotifytools_fprintf(stderr, event, "in %w, file %f had event(s): %.e\n");
   // suppose the file 'myfile' in mydir was read from and closed.  Then,
   // this prints to standard error something like:
   // "in mydir/, file myfile had event(s): CLOSE_NOWRITE.CLOSE.ISDIR\n"

Definition at line 1707 of file inotifytools.c.

References inotifytools_fprintf(), and inotifytools_sprintf().

Referenced by inotifytools_fprintf(), and inotifytools_printf().

int inotifytools_get_max_queued_events ( )

Get the event queue size.

This setting can also be read or modified by accessing the file /proc/sys/fs/inotify/max_queued_events.

Returns:: the maximum number of events which will be queued in the kernel.

Definition at line 1955 of file inotifytools.c.

References inotifytools_get_max_queued_events().

Referenced by inotifytools_get_max_queued_events().

int inotifytools_get_max_user_instances ( )

Get the maximum number of user instances of inotify.

This setting can also be read or modified by accessing the file /proc/sys/fs/inotify/max_user_instances.

Returns:: the maximum number of inotify file descriptors a single user can obtain.

Definition at line 1970 of file inotifytools.c.

References inotifytools_get_max_user_instances().

Referenced by inotifytools_get_max_user_instances().

int inotifytools_get_max_user_watches ( )

Get the maximum number of user watches.

This setting can also be read or modified by accessing the file /proc/sys/fs/inotify/max_user_watches.

Returns:: the maximum number of inotify watches a single user can obtain per inotify instance.

Definition at line 1985 of file inotifytools.c.

References inotifytools_get_max_user_watches().

Referenced by inotifytools_get_max_user_watches().

int inotifytools_get_num_watches ( )

Get the number of watches set up through libinotifytools.

Returns:: number of watches set up by inotifytools_watch_file(), inotifytools_watch_files() and inotifytools_watch_recursively().

Definition at line 1616 of file inotifytools.c.

References inotifytools_get_num_watches().

Referenced by inotifytools_get_num_watches().

int inotifytools_get_stat_by_filename	(	char const *	filename,
		int	event
	)

Get statistics by a particular filename.

inotifytools_initialize_stats() must be called before this function can be used.

Parameters:

filename	name of file to get stats for.
event	a single inotify event to get statistics for, or 0 for event total. See section Events.

Returns:: the number of times the event specified by event has occurred on the file specified by filename since stats collection was enabled, or -1 if the file is not being watched or event is invalid.

Note:: The filename specified must always be the original name used to establish the watch.

Definition at line 1574 of file inotifytools.c.

References inotifytools_get_stat_by_filename(), inotifytools_get_stat_by_wd(), and inotifytools_wd_from_filename().

Referenced by inotifytools_get_stat_by_filename().

int inotifytools_get_stat_by_wd	(	int	wd,
		int	event
	)

Get statistics by a particular watch descriptor.

inotifytools_initialize_stats() must be called before this function can be used.

Parameters:

wd	watch descriptor to get stats for.
event	a single inotify event to get statistics for, or 0 for event total. See section Events.

Returns:: the number of times the event specified by event has occurred on the watch descriptor specified by wd since stats collection was enabled, or -1 if event or wd are invalid.

Definition at line 1497 of file inotifytools.c.

References inotifytools_get_stat_by_wd().

Referenced by inotifytools_get_stat_by_filename(), and inotifytools_get_stat_by_wd().

int inotifytools_get_stat_total ( int event )

Get statistics aggregated across all watches.

inotifytools_initialize_stats() must be called before this function can be used.

Parameters:

event a single inotify event to get statistics for, or 0 for event total. See section Events.

Returns:: the number of times the event specified by event has occurred over all watches since stats collection was enabled, or -1 if event is not a valid event.

Definition at line 1520 of file inotifytools.c.

References inotifytools_get_stat_total().

Referenced by inotifytools_get_stat_total().

int inotifytools_ignore_events_by_regex	(	char const *	pattern,
		int	flags
	)

Ignore inotify events matching a particular regular expression.

pattern is a regular expression and flags is a bitwise combination of POSIX regular expression flags.

On future calls to inotifytools_next_events() or inotifytools_next_event(), the regular expression is executed on the filename of files on which events occur. If the regular expression matches, the matched event will be ignored.

Definition at line 2002 of file inotifytools.c.

References inotifytools_ignore_events_by_regex().

Referenced by inotifytools_ignore_events_by_regex().

int inotifytools_initialize ( )

Initialise inotify.

You must call this function before using any function which adds or removes watches or attempts to access any information about watches.

Returns:: 1 on success, 0 on failure. On failure, the error can be obtained from inotifytools_error().

Definition at line 281 of file inotifytools.c.

References inotifytools_initialize().

Referenced by inotifytools_initialize().

void inotifytools_initialize_stats ( )

Initialize or reset statistics.

inotifytools_initialize() must be called before this function can be used.

When this function is called, all subsequent events will be tallied. Statistics can then be obtained via the inotifytools_get_stat_* functions.

After the first call, subsequent calls to this function will reset the event tallies to 0.

Definition at line 418 of file inotifytools.c.

References inotifytools_initialize_stats().

Referenced by inotifytools_initialize_stats().

struct inotify_event* inotifytools_next_event ( int timeout )

read

Get the next inotify event to occur.

inotifytools_initialize() must be called before this function can be used.

Parameters:

timeout maximum amount of time, in seconds, to wait for an event. If timeout is 0, the function is non-blocking. If timeout is negative, the function will block until an event occurs.

Returns:: pointer to an inotify event, or NULL if function timed out before an event occurred. The event is located in static storage and it may be overwritten in subsequent calls; do not call free() on it, and make a copy if you want to keep it.

Note:: Your program should call this function or inotifytools_next_events() frequently; between calls to this function, inotify events will be queued in the kernel, and eventually the queue will overflow and you will miss some events.; If the function inotifytools_ignore_events_by_regex() has been called with a non-NULL parameter, this function will not return on events which match the regular expression passed to that function. However, the timeout period begins again each time a matching event occurs.

Definition at line 1040 of file inotifytools.c.

References inotifytools_next_event(), and inotifytools_next_events().

Referenced by inotifytools_next_event().

struct inotify_event* inotifytools_next_events	(	int	timeout,
		int	num_events
	)

read

Get the next inotify events to occur.

inotifytools_initialize() must be called before this function can be used.

Parameters:

timeout maximum amount of time, in seconds, to wait for an event. If timeout is 0, the function is non-blocking. If timeout is negative, the function will block until an event occurs.

num_events approximate number of inotify events to wait for until this function returns. Use this for buffering reads to inotify if you expect to receive large amounts of events. You are NOT guaranteed that this number of events will actually be read; instead, you are guaranteed that the number of bytes read from inotify is num_events * sizeof(struct inotify_event). Obviously the larger this number is, the greater the latency between when an event occurs and when you'll know about it. May not be larger than 4096.

Returns:: pointer to an inotify event, or NULL if function timed out before an event occurred or num_events < 1. The event is located in static storage and it may be overwritten in subsequent calls; do not call free() on it, and make a copy if you want to keep it. When num_events is greater than 1, this will return a pointer to the first event only, and you MUST call this function again to get pointers to subsequent events; don't try to add to the pointer to find the next events or you will run into trouble.

Note:: You may actually get different events with different values of num_events. This is because inotify does some in-kernel filtering of duplicate events, meaning some duplicate events will not be reported if num_events > 1. For some purposes this is fine, but for others (such as gathering accurate statistics on numbers of event occurrences) you must call this function with num_events = 1, or simply use inotifytools_next_event().; Your program should call this function or inotifytools_next_events() frequently; between calls to this function, inotify events will be queued in the kernel, and eventually the queue will overflow and you will miss some events.; If the function inotifytools_ignore_events_by_regex() has been called with a non-NULL parameter, this function will not return on events which match the regular expression passed to that function. However, the timeout period begins again each time a matching event occurs.

Definition at line 1094 of file inotifytools.c.

References inotifytools_next_events().

Referenced by inotifytools_next_event(), and inotifytools_next_events().

int inotifytools_printf	(	struct inotify_event *	event,
		char *	fmt
	)

Print a string to standard out using an inotify_event and a printf-like syntax. The string written will only ever be up to 4096 characters in length.

Parameters:

event	the event to use to construct a string.
fmt	the format string used to construct a string.

Returns:: number of characters written, or -1 if an error occurs.

Format string syntax

The following tokens will be replaced with the specified string:

%w - This will be replaced with the name of the Watched file on which an event occurred.
%f - When an event occurs within a directory, this will be replaced with the name of the File which caused the event to occur. Otherwise, this will be replaced with an empty string.
%e - Replaced with the Event(s) which occurred, comma-separated.
%Xe - Replaced with the Event(s) which occurred, separated by whichever character is in the place of `X'.
%T - Replaced by the current Time in the format specified by the string previously passed to inotifytools_set_printf_timefmt(), or replaced with an empty string if that function has never been called.

Example

   // suppose this is the only file watched.
   inotifytools_watch_file( "mydir/", IN_CLOSE );
  
   // wait until an event occurs
   struct inotify_event * event = inotifytools_next_event( -1 );
  
   inotifytools_printf(stderr, event, "in %w, file %f had event(s): %.e\n");
   // suppose the file 'myfile' in mydir was read from and closed.  Then,
   // this prints to standard out something like:
   // "in mydir/, file myfile had event(s): CLOSE_NOWRITE.CLOSE.ISDIR\n"

Definition at line 1662 of file inotifytools.c.

References inotifytools_fprintf(), and inotifytools_printf().

Referenced by inotifytools_printf().

int inotifytools_remove_watch_by_filename ( char const * filename )

Remove a watch on a file specified by filename.

Parameters:

filename Name of file on which watch should be removed.

Returns:: 1 on success, 0 on failure. On failure, the error can be obtained from inotifytools_error().

Note:: The filename specified must always be the original name used to establish the watch.

Definition at line 932 of file inotifytools.c.

References inotifytools_remove_watch_by_filename().

Referenced by inotifytools_remove_watch_by_filename().

int inotifytools_remove_watch_by_wd ( int wd )

Remove a watch on a file specified by watch descriptor.

inotifytools_initialize() must be called before this function can be used.

Parameters:

wd	Watch descriptor of watch to be removed.

Returns:: 1 on success, 0 on failure. If the given watch doesn't exist, returns 1. On failure, the error can be obtained from inotifytools_error().

Definition at line 909 of file inotifytools.c.

References inotifytools_remove_watch_by_wd().

Referenced by inotifytools_remove_watch_by_wd().

void inotifytools_replace_filename	(	char const *	oldname,
		char const *	newname
	)

Replace a certain filename prefix on all watches.

This function should be used to update filenames for an entire directory tree when a directory is known to have been moved or renamed. At the moment, libinotifytools does not automatically handle this situation.

inotifytools_initialize() must be called before this function can be used.

Parameters:

oldname	Current filename prefix.
newname	New filename prefix.

Example

   // if /home/user1/original_dir is moved to /home/user2/new_dir, then to
   // update all watches:
   inotifytools_replace_filename( "/home/user1/original_dir",
                                  "/home/user2/new_dir" );

Definition at line 859 of file inotifytools.c.

References inotifytools_replace_filename().

Referenced by inotifytools_replace_filename().

void inotifytools_set_filename_by_filename	(	char const *	oldname,
		char const *	newname
	)

Set the filename for one or more watches with a particular existing filename.

This function should be used to update a filename when a file is known to have been moved or renamed. At the moment, libinotifytools does not automatically handle this situation.

inotifytools_initialize() must be called before this function can be used.

Parameters:

oldname	Current filename.
newname	New filename.

Definition at line 829 of file inotifytools.c.

References inotifytools_set_filename_by_filename().

Referenced by inotifytools_set_filename_by_filename().

void inotifytools_set_filename_by_wd	(	int	wd,
		char const *	filename
	)

Set the filename for a particular watch descriptor.

This function should be used to update a filename when a file is known to have been moved or renamed. At the moment, libinotifytools does not automatically handle this situation.

inotifytools_initialize() must be called before this function can be used.

Parameters:

wd	Watch descriptor.
filename	New filename.

Definition at line 807 of file inotifytools.c.

References inotifytools_set_filename_by_wd().

Referenced by inotifytools_set_filename_by_wd().

void inotifytools_set_printf_timefmt ( char * fmt )

Set time format for printf functions.

Parameters:

fmt	A format string valid for use with strftime, or NULL. If NULL, time substitutions will no longer be made in printf functions. Note that this format string is not validated at all; using an incorrect format string will cause the printf functions to give incorrect results.

Definition at line 1943 of file inotifytools.c.

References inotifytools_set_printf_timefmt().

Referenced by inotifytools_set_printf_timefmt().

int inotifytools_snprintf	(	char *	out,
		int	size,
		struct inotify_event *	event,
		char *	fmt
	)

Construct a string using an inotify_event and a printf-like syntax. The string can only ever be up to 4096 characters in length.

Parameters:

out	location in which to store string.
size	maximum amount of characters to write.
event	the event to use to construct a string.
fmt	the format string used to construct a string.

Returns:: number of characters written, or -1 if an error occurs.

Format string syntax

The following tokens will be replaced with the specified string:

%w - This will be replaced with the name of the Watched file on which an event occurred.
%f - When an event occurs within a directory, this will be replaced with the name of the File which caused the event to occur. Otherwise, this will be replaced with an empty string.
%e - Replaced with the Event(s) which occurred, comma-separated.
%Xe - Replaced with the Event(s) which occurred, separated by whichever character is in the place of `X'.
%T - Replaced by the current Time in the format specified by the string previously passed to inotifytools_set_printf_timefmt(), or replaced with an empty string if that function has never been called.

Example

   // suppose this is the only file watched.
   inotifytools_watch_file( "mydir/", IN_CLOSE );
  
   // wait until an event occurs
   struct inotify_event * event = inotifytools_next_event( -1 );
  
   char mystring[1024];
   inotifytools_snprintf( mystring, 1024, event,
                          "in %w, file %f had event(s): %.e\n" );
   printf( mystring );
   // suppose the file 'myfile' in mydir was written to and closed.  Then,
   // this prints something like:
   // "in mydir/, file myfile had event(s): CLOSE_WRITE.CLOSE.ISDIR\n"

Definition at line 1816 of file inotifytools.c.

References inotifytools_event_to_str(), inotifytools_event_to_str_sep(), inotifytools_filename_from_wd(), and inotifytools_snprintf().

Referenced by inotifytools_snprintf(), and inotifytools_sprintf().

int inotifytools_sprintf	(	char *	out,
		struct inotify_event *	event,
		char *	fmt
	)

Construct a string using an inotify_event and a printf-like syntax. The string can only ever be up to 4096 characters in length.

This function will keep writing until it reaches 4096 characters. If your allocated array is not large enough to hold the entire string, your program may crash. inotifytools_snprintf() is safer and you should use it where possible.

Parameters:

out	location in which to store string.
event	the event to use to construct a string.
fmt	the format string used to construct a string.

Returns:: number of characters written, or -1 if an error occurs.

Format string syntax

The following tokens will be replaced with the specified string:

%w - This will be replaced with the name of the Watched file on which an event occurred.
%f - When an event occurs within a directory, this will be replaced with the name of the File which caused the event to occur. Otherwise, this will be replaced with an empty string.
%e - Replaced with the Event(s) which occurred, comma-separated.
%Xe - Replaced with the Event(s) which occurred, separated by whichever character is in the place of `X'.
%T - Replaced by the current Time in the format specified by the string previously passed to inotifytools_set_printf_timefmt(), or replaced with an empty string if that function has never been called.

Example

   // suppose this is the only file watched.
   inotifytools_watch_file( "mydir/", IN_CLOSE );
  
   // wait until an event occurs
   struct inotify_event * event = inotifytools_next_event( -1 );
  
   char mystring[1024];
   // hope this doesn't crash - if filename is really long, might not fit into
   // mystring!
   inotifytools_sprintf(mystring, event, "in %w, file %f had event(s): %.e\n");
   printf( mystring );
   // suppose the file 'myfile' in mydir was written to and closed.  Then,
   // this prints something like:
   // "in mydir/, file myfile had event(s): CLOSE_WRITE.CLOSE.ISDIR\n"

Definition at line 1765 of file inotifytools.c.

References inotifytools_snprintf(), and inotifytools_sprintf().

Referenced by inotifytools_fprintf(), and inotifytools_sprintf().

int inotifytools_str_to_event ( char const * event )

Convert comma-separated events from string form to integer form (as in inotify.h).

Parameters:

event a sequence of events in string form as defined in inotify.h without leading IN_ prefix (e.g., MODIFY, ATTRIB), comma-separated. Case insensitive. Can be a single event. Can be empty or NULL. See section Events.

Returns:: integer representing the mask specified by event, or 0 if any string in event is empty or NULL, or -1 if any string in event does not match any event.

Example

   char * eventstr = "MODIFY,CLOSE,CREATE";
   int eventnum = inotifytools_str_to_event( eventstr );
   if ( eventnum == IN_MODIFY | IN_CLOSE | IN_CREATE ) {
      printf( "This code always gets executed!\n" );
   }

Definition at line 541 of file inotifytools.c.

References inotifytools_str_to_event(), and inotifytools_str_to_event_sep().

Referenced by inotifytools_str_to_event().

int inotifytools_str_to_event_sep	(	char const *	event,
		char	sep
	)

Convert character separated events from string form to integer form (as in inotify.h).

Parameters:

event	a sequence of events in string form as defined in inotify.h without leading IN_ prefix (e.g., MODIFY, ATTRIB), separated by the sep character. Case insensitive. Can be a single event. Can be empty or NULL. See section Events.
sep	Character used to separate events. sep must not be a character in a-z, A-Z, or _.

Returns:: integer representing the mask specified by event, or 0 if any string in event is empty or NULL, or -1 if any string in event does not match any event or sep is invalid.

Example

   char * eventstr = "MODIFY:CLOSE:CREATE";
   int eventnum = inotifytools_str_to_event_sep( eventstr, ':' );
   if ( eventnum == IN_MODIFY | IN_CLOSE | IN_CREATE ) {
      printf( "This code always gets executed!\n" );
   }

Definition at line 471 of file inotifytools.c.

References inotifytools_str_to_event_sep().

Referenced by inotifytools_str_to_event(), and inotifytools_str_to_event_sep().

int inotifytools_watch_file	(	char const *	filename,
		int	events
	)

Set up a watch on a file.

Parameters:

filename	Absolute or relative path of file to watch.
events	bitwise ORed inotify events to watch for. See section Events.

Returns:: 1 on success, 0 on failure. On failure, the error can be obtained from inotifytools_error().

Definition at line 955 of file inotifytools.c.

References inotifytools_watch_file(), and inotifytools_watch_files().

Referenced by inotifytools_watch_file(), and inotifytools_watch_recursively_with_exclude().

int inotifytools_watch_files	(	char const *	filenames[],
		int	events
	)

Set up a watch on a list of files.

inotifytools_initialize() must be called before this function can be used.

Parameters:

filenames	null-terminated array of absolute or relative paths of files to watch.
events	bitwise OR'ed inotify events to watch for. See section Events.

Returns:: 1 on success, 0 on failure. On failure, the error can be obtained from inotifytools_error().

Definition at line 977 of file inotifytools.c.

References inotifytools_watch_files().

Referenced by inotifytools_watch_file(), and inotifytools_watch_files().

int inotifytools_watch_recursively	(	char const *	path,
		int	events
	)

Set up recursive watches on an entire directory tree.

inotifytools_initialize() must be called before this function can be used.

Parameters:

path	path of directory or file to watch. If the path is a directory, every subdirectory will also be watched for the same events up to the maximum readable depth. If the path is a file, the file is watched exactly as if inotifytools_watch_file() were used.
events	Inotify events to watch for. See section Events.

Returns:: 1 on success, 0 on failure. On failure, the error can be obtained from inotifytools_error(). Note that some errors on subdirectories will be ignored; for example, if you watch a directory tree which contains some directories which you do not have access to, those directories will not be watched, but this function will still return 1 if no other errors occur.

Note:: This function does not attempt to work atomically. If you use this function to watch a directory tree and files or directories are being created or removed within that directory tree, there are no guarantees as to whether or not those files will be watched.

Definition at line 1248 of file inotifytools.c.

References inotifytools_watch_recursively(), and inotifytools_watch_recursively_with_exclude().

Referenced by inotifytools_watch_recursively().

int inotifytools_watch_recursively_with_exclude	(	char const *	path,
		int	events,
		char const **	exclude_list
	)

Set up recursive watches on an entire directory tree, optionally excluding some directories.

inotifytools_initialize() must be called before this function can be used.

Author:: UH

Parameters:

path	path of directory or file to watch. If the path is a directory, every subdirectory will also be watched for the same events up to the maximum readable depth. If the path is a file, the file is watched exactly as if inotifytools_watch_file() were used.
exclude_list	NULL terminated path list of directories not to watch. Can be NULL if no paths are to be excluded. Directories may or may not include a trailing '/'.
events	Inotify events to watch for. See section Events.

Returns:: 1 on success, 0 on failure. On failure, the error can be obtained from inotifytools_error(). Note that some errors on subdirectories will be ignored; for example, if you watch a directory tree which contains some directories which you do not have access to, those directories will not be watched, but this function will still return 1 if no other errors occur.

Note:: This function does not attempt to work atomically. If you use this function to watch a directory tree and files or directories are being created or removed within that directory tree, there are no guarantees as to whether or not those files will be watched.

Definition at line 1284 of file inotifytools.c.

References inotifytools_watch_file(), and inotifytools_watch_recursively_with_exclude().

Referenced by inotifytools_watch_recursively(), and inotifytools_watch_recursively_with_exclude().

int inotifytools_wd_from_filename ( char const * filename )

Get the watch descriptor for a particular filename.

inotifytools_initialize() must be called before this function can be used.

Parameters:

filename file name to find watch descriptor for.