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Example of Environment variables in Linux

1. export command is used to set environment variables.
2. ech $variable is used to print value on command line.
3. getenv() library function is used to access the value from any C/C++ program.
4. We can view all environment variables using command 'env | more'.
5. 'unset' command is used to delete exported variales.
6. There should not be any space after = (i.e export MYVAR= cppbuzz.com is wrong, it should be export MYVAR=cppbuzz.com).

Syntax to export environment variables

export MYVAR=cppbuzz.com

Print environment variables

echo $MYVAR

Unset/Delete environment variables

unset MYVAR

Print all environment variables

env | more
environement variables in linux & c++

Accessing Environment variables in C++

getenv() is a library function which is used to read the env variables. Below example is in C++, but you can also call this function in C programming.

using namespace std;

int main()
cout<<"\n value of MYVAR is :"<<getenv("MYVAR")<<":"<<endl;
return 0;
environement variables in linux & c++

Video on Environment variables