StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
primarykey
Id
13290134
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
5
CommunityOwnedDate
CreationDate
2012-11-08T13:43:28.493
FavoriteCount
0
LastActivityDate
2015-07-10T22:08:46.697
LastEditDate
2015-07-10T22:08:46.697
LastEditorUserId
937324
OwnerUserId
1806269
ParentId
6015498
PostTypeId
2
Score
13
ViewCount
0
LastEditorDisplayName
text
Body
<a href="http://www.gnu.org/software/libc/manual/html_node/Signal-Handling.html" rel="nofollow noreferrer">The GNU C Library Reference Manual</a> has a whole chapter explaining everything about signal handling. You always get the previously set signal handler (a function pointer) when you install your own handler (see manpages for <code>signal()</code> or <code>sigaction()</code>). <pre><code>previous_handler = signal(SIGINT, myhandler); </code></pre> The general rule is, that you can always reset to the previous handler and <code>raise()</code> the signal again. <pre><code>void myhandler(int sig) { /* own stuff .. */ signal(sig, previous_handler); raise(sig); /* when it returns here .. set our signal handler again */ signal(sig, myhandler); } </code></pre> There is one disadvantage of the general rule: Hardware exceptions which are mapped to signals are usually assigned to a certain instruction which caused the exception. So, when you raise a signal again, the associated instruction is not the same as originally. This can but should not harm other signal handlers. Another disadvantage is, that each raised signal causes a lot of processing time. To prevent excessive use of <code>raise()</code> you can use the following alternatives: <ol> <li>In case of <code>SIG_DFL</code> the function pointer points to address <code>0</code> (which is obviously no valid address). Thus, you have to reset the handler and <code>raise()</code> the signal again. <pre><code>if (previous_handler == SIG_DFL) { signal(sig, SIG_DFL); raise(sig); signal(sig, myhandler); } </code></pre></li> <li><code>SIG_IGN</code> has value <code>1</code> (also an invalid address). Here you can just return (do nothing). <pre><code>else if (previous_handler == SIG_IGN) { return; } </code></pre></li> <li>Otherwise (neither <code>SIG_IGN</code> nor <code>SIG_DFL</code>) you have received a valid function pointer and you can call the handler directly, <pre><code>else { previous_handler(sig); }</code></pre></li> </ol> Of course, you have to consider the different APIs as well (see manpages for <code>signal()</code> and <code>sigaction()</code>).
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POexecuting default signal handler
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USGabriel Southern
UserOwnerUserId
1. UShomac
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
2. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId
1. This table or related slice is empty.

Querying!

Guidance

A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.