flux_stat_watcher_create(3)

SYNOPSIS

#include <flux/core.h>

typedef void (*flux_watcher_f)(flux_reactor_t *r,
                               flux_watcher_t *w,
                               int revents,
                               void *arg);

flux_watcher_t *flux_stat_watcher_create (flux_reactor_t *r,
                                          const char *path,
                                          double interval,
                                          flux_watcher_f callback,
                                          void *arg);

int flux_stat_watcher_get_rstat (flux_watcher_t *w,
                                 struct stat *stat,
                                 struct stat *prev);

Link with -lflux-core.

DESCRIPTION

flux_stat_watcher_create() creates a reactor watcher that monitors for changes in the status of the file system object represented by path. If the file system object exists, inotify(7) is used, if available; otherwise the reactor polls the file every interval seconds. A value of zero selects a conservative default (currently five seconds).

The callback revents argument should be ignored.

flux_stat_watcher_get_rstat() may be used to obtain the status within callback. If non-NULL, stat receives the current status. If non-NULL, prev receives the previous status.

If the object does not exist, stat->st_nlink will be zero and other status fields are undefined. The appearance/disappearance of a file is considered a status change like any other.