[Reprint]linux environment variable setting method summary (Path/ld_library_path)

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path: The lookup path to the executable program
To view the current environment variables:
Echo $PATH
Set up:
Method One: Export path=path:/xxx but fails after logout
Method Two: Modify the ~/.BASHRC or ~/.bash_profile or system level/etc/profile
1. Add For example export Path=/opt/activepython-2.7/bin: $PATH
2. Source. BASHRC (The source command is also known as a "point command", which is a dot symbol (.).) The source command is typically used to re-execute a newly modified initialization file for immediate effect without having to log off and log back in.
Ld_library_path: Find path for dynamic libraries
Set up:
Method One: Export ld_library_path=ld_library_path:/xxx but fails after logout
Method Two: Modify the ~/.BASHRC or ~/.bash_profile or system level/etc/profile
1. Add For example export path=/opt/activep/lib: $LD _library_path
2. Source. BASHRC (The source command is also known as a "point command", which is a dot symbol (.).) The source command is typically used to re-execute a newly modified initialization file for immediate effect without having to log off and log back in.
Method Three: This is not modified Ld_library_path but the effect is the same as the implementation of dynamic library search,
1. Add a line below/etc/ld.so.conf/usr/local/mysql/lib
2. Save after Ldconfig (the purpose of the Ldconfig command, mainly in the default search directory (/lib and/usr/lib) and dynamic Library configuration file/etc/ld.so.conf listed in the directory, the search for a shareable dynamic link library (format as described above, lib*.so*) to create the connection and cache files required for the dynamic loader (ld.so). The cache file defaults to/etc/ld.so.cache, which holds the list of queued dynamic-link library names.)
Method Three is slightly cumbersome, and the benefit is that the comparison is not restricted by the user.
For example:
The Ld_library_path for user production is analyzed as follows:
1.[email protected]:~> Echo $LD _library_path
/home/production/cpst/cptools/lib:/home/production/cpst/campost/lib:/home/production/tuxedo/lib:/home/ production/tuxedo/jre/lib/amd64/server:/home/production/tuxedo/jre/jre/bin:/usr/lib:/usr/lib64:/lib:/lib64:/ Usr/local/lib:/usr/local/lib64:/oracle/product/11gr2/db/lib:/oracle/product/11gr2/db/ctx/lib
2. View. Profile:
The. Profile has:. ~/cpst/campost/config/setenv, stating that user startup is running script setenv.
3. The setenv has:
Export Campost_home= $HOME/cpst/campost
Export cptools_root= $HOME/cpst/cptools
Export ld_library_path= $CPTOOLS _root/lib: $CAMPOST _home/lib: $LD _library_path
4, setenv in the $ld_library_path, into the root view:
(1) africa:~ # echo $LD _library_path
/usr/lib:/usr/lib64:/lib:/lib64:/usr/local/lib:/usr/local/lib64:/oracle/product/11gr2/db/lib:/oracle/product/ 11gr2/db/ctx/lib
(2) The Etc/profile are:
Export ld_library_path=/usr/lib:/usr/lib64:/lib:/lib64:/usr/local/lib:/usr/local/lib64: $LD _library_path
(3) The/etc/profile.d/oracle.sh are:
ld_library_path=${ld_library_path:+ $LD _library_path:} $ORACLE _home/lib: $ORACLE _home/ctx/lib

[Reprint]linux environment variable setting method summary (Path/ld_library_path)