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iPhone call log / history

由 给你一囗甜甜゛ 提交于 2019-11-26 02:34:07
问题 I\'m doing some research on the feasibility of an iPhone application, and can\'t find any indication in Apple\'s documentation that an iPhone app can read the call history of the phone, specifically the number called, when, and the duration... I also need the same information for SMS. First of all: I\'ve done my research and googled around, searched around on this site! I know this question had been asked a lot of times before, and the answer was always: \"It can\'t be done\" (at least not on

When was the NULL macro not 0?

由 為{幸葍}努か 提交于 2019-11-26 02:00:12
问题 I vaguely remember reading about this a couple of years ago, but I can\'t find any reference on the net. Can you give me an example where the NULL macro didn\'t expand to 0? Edit for clarity: Today it expands to either ((void *)0) , (0) , or (0L) . However, there were architectures long forgotten where this wasn\'t true, and NULL expanded to a different address. Something like #ifdef UNIVAC #define NULL (0xffff) #endif I\'m looking for an example of such a machine. Update to address the

What is the point of DBNull?

由 百般思念 提交于 2019-11-26 01:56:40
In .NET there is the null reference, which is used everywhere to denote that an object reference is empty, and then there is the DBNull , which is used by database drivers (and few others) to denote... pretty much the same thing. Naturally, this creates a lot of confusion and conversion routines have to be churned out, etc. So why did the original .NET authors decide to make this? To me it makes no sense. Their documentation makes no sense either: The DBNull class represents a nonexistent value. In a database, for example, a column in a row of a table might not contain any data whatsoever.

System where 1 byte != 8 bit? [duplicate]

由 拟墨画扇 提交于 2019-11-26 01:27:51
问题 This question already has an answer here: What platforms have something other than 8-bit char? 12 answers All the time I read sentences like don\'t rely on 1 byte being 8 bit in size use CHAR_BIT instead of 8 as a constant to convert between bits and bytes et cetera. What real life systems are there today, where this holds true? (I\'m not sure if there are differences between C and C++ regarding this, or if it\'s actually language agnostic. Please retag if neccessary.) 回答1: On older machines,

What is the point of DBNull?

由 我是研究僧i 提交于 2019-11-26 00:59:57
问题 In .NET there is the null reference, which is used everywhere to denote that an object reference is empty, and then there is the DBNull , which is used by database drivers (and few others) to denote... pretty much the same thing. Naturally, this creates a lot of confusion and conversion routines have to be churned out, etc. So why did the original .NET authors decide to make this? To me it makes no sense. Their documentation makes no sense either: The DBNull class represents a nonexistent

zabbix系列zabbix3.4监控rabbitmq

由 一世执手 提交于 2019-11-25 23:39:49
rabbitmq3.6.10版本 rabbitmq监控要点 具体监控什么东西，主要是rabbitmq-web监控页面的overview内容 还有就是队列堆积数，如果超过某个数值，比如5000个就立马报警 添加rabbitmq脚本 [root@test-mq02 ~]# ll -al /etc/zabbix/script/rabbitmq/ total 44 drwxr-xr-x 2 root root 4096 Feb 6 11:22 . drwxr-xr-x 3 root root 4096 Feb 1 15:48 .. -rwxr-xr-x 1 root root 13155 Feb 1 16:29 api.py -rwxr-xr-x 1 root root 424 Jul 21 2017 list_rabbit_nodes.sh -rwxr-xr-x 1 root root 426 Jul 21 2017 list_rabbit_queues.sh -rwxr-xr-x 1 root root 430 Jul 21 2017 list_rabbit_shovels.sh -rw-r--r-- 1 root root 138 Feb 6 11:22 .rab.auth -rwxr-xr-x 1 root root 782 Jul 21 2017 rabbitmq-status

Linux系统history命令小技巧

由 谁说胖子不能爱 提交于 2019-11-25 22:36:56
背景 Linux系统中的history命令可以查看在系统中执行过哪些命令，在系统被***后，可以查看系统中执行过哪命令，有助于分析相关问题。 知识点 在Linux系统执行history #history命令 711 alias 712 history 713 ls ~/.bash_history 714 history 系统中使用过的命令保存在/root/.bash_history目录下 [root@localhost ~]# ls /root/.bash_history /root/.bash_history [root@localhost ~]# cat /root/.bash_history 系统默认保存1000条使用过的命令，由系统的环境变量HISTSIZE来就决定的 [root@liuleilinux ~]# echo $HISTSIZE 1000 而HISTSIZE环境变量值的大小可通过修改/etc/profile配置文件 [root@localhost ~]# vim /etc/profile history -c 空保存在内存中的系统历史命令 [root@localhost ~]# history -c [root@localhost ~]# history 1 history 但不能清空配置文件.bash_history中的记录
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