[pro test feasible] error while loading shared libraries solution

▚ 01  Problem description & analysis

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• stay Linux in , When compiling or installing packages , We often encounter similar problems ：

error while loading shared libraries: libxxx.so: cannot open shared object file: No such file or directory

• The reason for this problem is often not the absence of this file , Instead, the path is not configured , Therefore, an error will be reported when compiling because the file cannot be found .

This article assumes that the library not found is libmpfr.so.6, The absolute path is /home/dabai/mpfr-4.0.2/lib
There are two common solutions .

▚ 02  Method 1 ： Use export command

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• Terminal use export Command to configure environment variables , But only limited to the current terminal ; For other terminal windows, you need to reuse export Orders work .
• export The format of the configuration environment variable is ：

export LD_LIBRARY_PATH=/home/dabai/mpfr-4.0.2/lib:$LD_LIBRARY_PATH

• among ,LD_LIBRARY_PATH yes Linux Environment variable name , This environment variable is mainly used to specify the search of shared libraries （ Dynamic link library ） In addition to the default path .

▚ 03  Method 2 ： Modify the configuration file

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• Modify the configuration file , Such as ~/.bashrc or ~/.bash_profile or /etc/profile.
• among , Ordinary users It can be modified directly ~/.bashrc or ~/.bash_profile, therefore , This modification is only valid for the current user .
• root user Modifiable /etc/profile, And it is effective for all users .

• Let's modify ~/.bashrc File as an example ：

vim ~/.bashrc

• then , stay .bashrc Add the following to the file ：

export LD_LIBRARY_PATH=/home/dabai/mpfr-4.0.2/lib:$LD_LIBRARY_PATH

• After saving and exiting , Enter the following command at the terminal , To give effect to the above order ：

source ~/.bashrc