June 2025
Beginner to intermediate
1180 pages
37h 48m
English
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10.2 Running Processes under a Different Identity (su)
There are two restrictions on the execution of programs by ordinary users:
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Ordinary users are allowed to run only those processes where the access rights (owner, group, r, and x access bits) allow it. For ordinary programs, this is not a limitation. However, there are some system administration commands in the /usr/sbin directory, for example, that can only be started by root.
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Processes belong to the user who started them, as it were. This means that a process is allowed to access the same files as the user. Put another way, files that you as a user are not allowed to modify must also not be modified by programs that you start. Files newly created by the process also belong to the ...
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