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User: root (0)
PHP: 7.4.33
Disabled: passthru,exec,system,putenv,chroot,chgrp,chown,shell_exec,popen,proc_open,pcntl_exec,ini_alter,ini_restore,dl,openlog,syslog,readlink,symlink,popepassthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,imap_open,apache_setenv
$ pwd: /usr/share/cmake-3.28/Help/command/
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File: //usr/share/cmake-3.28/Help/command/UNSET_NOTE.txt
.. note::

  When evaluating :ref:`Variable References` of the form ``${VAR}``, CMake
  first searches for a normal variable with that name.  If no such normal
  variable exists, CMake will then search for a cache entry with that name.
  Because of this, **unsetting a normal variable can expose a cache variable
  that was previously hidden**.  To force a variable reference of the form
  ``${VAR}`` to return an empty string, use ``set(<variable> "")``, which
  clears the normal variable but leaves it defined.
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