Bash Learning Materials

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Bash (GNU Bourne-Again SHell) the default shell for many Linux distributions. It is very common for scripting languages in Linux. Bash is easy and straightforward for writing small tools. However, as most tools, it has its grammars that could easily cause bugs if they are not used correctly. Here I summarize a list of good
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How to get the running process’ parent process’ ID in C / C++?

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How to get the running process’ parent process’ ID in C / C++? In C and C++, you can call the getppid() library function which is a function from the POSIX library. #include <sys/types.h> #include <unistd.h> pid_t getppid(void); getppid() returns the process ID of the parent of the calling process. Example usage: getppid.c #include <stdio.h>
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How to delete or get the number in the tail from a string in shell script?

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How to delete or get the number in the tail from a string in shell script (bash script)? Okay to call other tools. For example, from “/dev/sda8”, I want to get “/dev/sda” and “8” separately. This can be achieved by using sed as follows. To get the string after deleting the tailing numbers, we can
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Floating Point in Bash Shell

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Integers are natively supported in Bash shell. However, what if we use floating point in Bash shell? The short and direct answer is using ‘bc‘ command – “An arbitrary precision calculator language.” Just run bc  and enter some floating point calculation expression, such as “1.2+8.2”, bc will give the result. In a script, we certainly
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Online Tutorials for Linux Beginners

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This post compiles a list of tutorials on the Internet for Linux beginners. Linux beginners usually get headache from the “seemed” complexity of the Linux operation system. But once they get into the gate and get familiar with Linux, they will love it. UNIX Tutorial for Beginners “A beginners guide to the Unix and Linux
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