c++ - to system() or fork()/exec()? -



c++ - to system() or fork()/exec()? -

there appear 2 mutual ways of running external executable c in unix,

system()

call and

pid = fork() switch(pid) //switch statement based on homecoming value of pid, //one branch of include , exec() command

is there reason prefer fork/exec on scheme in case functionally equivalent (parent process waits kid finish, no complex info returned child)?.

system executes command-interpreter, i.e. shell, (a) slower direct fork/exec, (b) may behave differently on different systems , (c) potential security hazard if pass string untrusted source. also, system waits kid process exit, while might want run concurrently parent process.

more in general, low-level fork/exec gives additional control: before or in between 2 operations, might want chdir, open pipes, close file descriptors, set shared memory, etc.

(by different systems, don't mean windows vs. unix (as windows doesn't have fork): i'm talking reddish hat linux vs. ubuntu. former uses bash execute passed system, latter lightweight posix-compatible shell.)

c++ c fork

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