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

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(2) 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.

RETURN VALUE

flux_stat_watcher_create() returns a flux_watcher_t object on success. On error, NULL is returned, and errno is set appropriately.

ERRORS

ENOMEM
Out of memory.

SEE ALSO

flux_watcher_start(3), flux_reactor_start(3), stat(2)

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