std::getenv

 

C++

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rel_ops::operator!= rel_ops::operator> rel_ops::operator<= rel_ops::operator>=

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system	getenv
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setjmp
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Types
jmp_buf

 

Defined in header <cstdlib>
const char *getenv( const char *env_var );

Searches for an environmental variable with name env_var in the host-specified environment list and returns information associated with it. The set of environmental variables and methods of altering it are implementation-defined.

Parameters

env_var

-

null-terminated character string identifying the name of the environmental variable to look for

Return value

Character string identifying the value of the environmental variable or NULL if such variable is not found.

Example

run this code

#include <iostream>
#include <cstdlib>
 
int main(int argc, char *argv[])
{
    std::cout << "Your PATH is: " << std::getenv("PATH") << std::endl;
}

Possible output:

Your PATH is: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games