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The core is the kernel of the unix system. When your program has memory out of bounds, the operating system will terminate your process and dump the current memory state to the core file for further analysis. Programmers can find out the problem through the core file. It records a detailed status description when the program hangs.
What is core dump? Core means memory, and Dump means throwing it out and heaping it out. When developing and using Unix programs, sometimes the program goes down inexplicably, but there is no prompt (sometimes it prompts core dumped). At this time, you can check whether there is a file in the form of core.process number. This file is the operation The system throws out the memory content when the program is down, and it can be used as a reference for debugging the program.
Core dump is also called core dump. When an exception occurs during the running of the program and the program exits abnormally, the operating system stores the current memory status of the program in a core file, which is called core dump. How to use the core file gdb -c core file path [the path of the application program], enter where and press Enter after entering, it can display which line of the program crashed and in which function.
Why is there no core file generated? The generation of the core file is related to the environment settings of your current system. You can use the following statement to set it up, and then run the program to generate the core file.
The location where the ulimit -c unlimited core file is generated is generally the same as the path of the running program, and the file name is generally core.process number.
Do you know if there is a problem with the program and a signal is generated without using the core file? Answer: The kernel sends a signal to the process.
Shared memory object mapping. What is the difference between the two: Difference: A memory-mapped file is a mapping from a file to a block of memory so that the application can access the file on the disk through the memor...
Select * from the table where (ID = 10) or (ID = 32) or (ID = 22) to retrieve the results in the order of 10, 32, 22? Select * from user_info Where (ID IN (10, 32, 22)) order BY FIND_IN_SET(ID, '10,32,22') Continuing...