This is proc/display_env.c (Listing 6-3, page 127), an example from the book, The Linux Programming Interface.
The source code file is copyright 2022, Michael Kerrisk, and is licensed under the GNU General Public License, version 3.
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/* display_env.c Display the process environment list. */ #include "tlpi_hdr.h" extern char **environ; /* Or define _GNU_SOURCE to get it from <unistd.h> */
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