07-03-2008
Usage of exit() inside a signal handler
Is it ok to use exit() inside a signal handler?
I catch SIGUSR1 in a signal handler and I try to close a file and then exit. The result is inconsistent. Sometimes the process exit and sometimes it returns to the original state before the signal handler was invoked.
Perhaps exit is not legal in a handler function?
T.
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LEARN ABOUT DEBIAN
semanage_iface_iterate
semanage_iterate(3) Libsemanage API documentation semanage_iterate(3)
NAME
semanage_iterate - SELinux Management API
SYNOPSIS
The following iterate function is supported for any semanage record.
Replace the function and object name as necessary.
extern int ITERATE_FUNCTION (
semanage_handle_t *handle,
int (*handler) (
const semanage_OBJECT_t *object,
void *varg),
void *handler_arg);
DESCRIPTION
Behavior:
The iterate function will execute the specified handler over all objects in the selected location. An arbitrary argument can be
passed into the handler function along with each object.
The object passed in is property of the libsemanage library, and may not be modified or preserved - use semanage_OBJECT_clone if
that is necessary.
The handler code may not invoke any semanage write requests for the same object type (i.e. modifying the underlying store is not
allowed). The iterate function is reentrant only while inside a transaction (see semanage_begin_transaction ). It is not safe to
execute other semanage read or write requests within iterate if not inside a transaction. The handler may return -1 to signal error
exit, 0 to signal continue, and 1 to signal successful exit early (the iterate function will stop accordingly).
Parameters:
The handle is used to track persistent state across semanage calls, and for error reporting. The handler is the function to execute,
with handler_arg as its second parameter, and each object as its first parameter.
Requirements:
This function requires an semanage connection to be established (see semanage_connect(3) )
RETURN VALUE
In case of failure, -1 is returned, and the semanage error callback is invoked, describing the error. Otherwise a non-negative integer is
returned (a commit number). The same number will be returned by all other semanage object read calls until the next commit.
SEE ALSO
semanage_handle_create(3), semanage_connect(3),
ivg2@cornell.edu 15 March 2006 semanage_iterate(3)