Getenv in c program

In particular, the POSIX functions setenv , unsetenv , and putenv would introduce a data race if called without synchronization. Character string identifying the value of the environmental variable or null pointer if such variable is not found.

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Program support utilities Program termination abort. This statement shows that the home path will be displayed until the value becomes NULL. The same goes for the other information.

Each value obtained will be printed later. Home, Path, and Log name will be displayed according to the default information. These all refer to the environment variable information. On execution of the code, we will see the resultant values. The results for the home path will display the user name in the directory. The second part was for the path of the environment.

The third line shows the log name or in actuality, the user name. Now, come toward the user choice, the resultant value is not present as it will not be found. So the null is returned:. This example will also display the path only but through a different approach. First, the value is fetched through the function, and then, the third fetched path will be displayed by applying an if-statement to check if each information is displayed until the resultant in the pointer is not NULL.

Now, see the resultant value through the terminal. You will see the path is displayed and obtained through the source code:. Getenv brings the environment in the form of different ways. Each approach is explained that helps to bring the path, user name, and root of the default environment of the Linux operating system.

We hope you found this article helpful. Check out more Linux Hint articles for useful tips and information. I am a self-motivated information technology professional with a passion for writing. I am a technical writer and love to write for all Linux flavors and Windows. In the C programming language, several functions help the user acquire relevant information, such as the process name and id. Similarly, in this article, we will discuss information about the environment list that contains the variable name of the environment and then returns the value in the form of a pointer.

If the function getenv cannot find the environment, it returns NULL, and errno displays the error message. Then we have a printf function that will prompt the user to enter the size of the array at run time.

In the C programming language, the scanf function is being used to identify characters or any other input from the user. Again we have a printf function that will prompt the user to enter the elements of the array at run time. In the C programming language, the for loop is used to repeat statements or parts of a program repeatedly. This enables them to write code once and then reuse it as needed, increasing the probability that the program will function as planned.

Again we have two printf statements that will display the minimum and a maximum value of the array on the screen. The black screen is presented and asks the user to enter the size and elements in the array. This article was all about the minimum function in the C programming language. However, as a bonus point, we have also utilized the max function in the example. The examples mentioned in this guide have been clarified in detail. I hope the user will have no trouble while using the min function in the C language.

They can be any numeric values, including pointers to almost the same base type, and then they can be an integer or floating-point values. The C program determines the smallest or least element in an array.