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Does shell script wait for completion?
wait is an inbuilt command in the Linux shell. It waits for the process to change its state i.e. it waits for any running process to complete and returns the exit status. Here, VLC is the process name. And 3868 is its Process ID.
Does a bash script wait for command to finish?
wait is a command that waits for the given jobs to complete and returns the exit status of the waited for command. Since the wait command affects the current shell execution environment, it is implemented as a built-in command in most shells.
What is exec in bash?
exec command in Linux is used to execute a command from the bash itself. This command does not create a new process it just replaces the bash with the command to be executed. If the exec command is successful, it does not return to the calling process.
How do you wait for a process to finish in Linux?
You can use the bash builtin wait : $ sleep 10 & [2] 28751 $ wait 28751 [2]- Done sleep 10 $ help wait wait: wait [-n] [id …] Wait for job completion and return exit status. Waits for each process identified by an ID, which may be a process ID or a job specification, and reports its termination status.
How do I add a delay in bash?
Linux Sleep Command (Pause a Bash Script) sleep is a command-line utility that allows you to suspends the calling process for a specified time. In other words, the sleep command pauses the execution of the next command for a given number of seconds.
Is there a way to wait for a process in Bash?
Unfortunately Bash’s support for that is limited – you can wait for one specific child process (and get its exit status) or you can wait for all of them, and always get a 0 result. What it appears impossible to do is the equivalent of waitpid(-1), which blocks until any child process returns.
How to wait for a process to finish Stack Overflow?
After setting /proc/sys/kernel/yama/ptrace_scope to 0, it is possible to use the strace program. Further switches can be used to make it silent, so that it really waits passively: This function will exits immediately, when all processes was terminated.
How to wait for child status in Bash?
Getting that child status is usually the job of the wait family of functions in the lower level POSIX APIs. Unfortunately Bash’s support for that is limited – you can wait for one specific child process (and get its exit status) or you can wait for all of them, and always get a 0 result.
How to wait for all jobs to finish?
Here is simple example using wait. Or just wait (without arguments) for all. This will wait for all jobs in the background are completed. If the -n option is supplied, waits for the next job to terminate and returns its exit status. See: help wait and help jobs for syntax.