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Q&A How can I schedule a later task in Python?

Use at to schedule the command, using subprocess from Python to invoke at. It doesn't even require shell=True. For example: import shlex, subprocess subprocess.run( # `at` command to run n...

posted 9mo ago by Karl Knechtel‭ · edited 9mo ago by Karl Knechtel‭

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#3: Post edited by

Karl Knechtel‭ · 2023-08-31T19:27:42Z (9 months ago)
use shlex.split per trichoplax's suggestion

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Use [`at`](https://en.wikipedia.org/wiki/At_%28command%29) to schedule the command, using `subprocess` from Python to invoke `at`. It doesn't even require `shell=True`. For example:
```
~~import subprocess~~
subprocess.run(
# `at` command to run now
~~"at now +10 minutes".split(),~~
# shell command that `at` will schedule, provided to `at`'s stdin
input="python -m this > this.txt",
# open stdin in text mode with the default encoding
text=True
)
```
<section class="notice is-warning">
The `at` program will detach itself from the terminal, so capturing stdout or stderr from the scheduled task will require a workaround (such as invoking `xterm`, or `tee`ing to a TTY that will be open when the task runs).
However, if local mail services are available, and `at` is run from a `su` shell, it will send local mail with the output when the job is completed. Check the man page for details.
</section>

Use [`at`](https://en.wikipedia.org/wiki/At_%28command%29) to schedule the command, using `subprocess` from Python to invoke `at`. It doesn't even require `shell=True`. For example:
```
import shlex, subprocess
subprocess.run(
# `at` command to run now
shlex.split("at now +10 minutes"),
# shell command that `at` will schedule, provided to `at`'s stdin
input="python -m this > this.txt",
# open stdin in text mode with the default encoding
text=True
)
```
<section class="notice is-warning">
The `at` program will detach itself from the terminal, so capturing stdout or stderr from the scheduled task will require a workaround (such as invoking `xterm`, or `tee`ing to a TTY that will be open when the task runs).
However, if local mail services are available, and `at` is run from a `su` shell, it will send local mail with the output when the job is completed. Check the man page for details.
</section>

#2: Post edited by

Karl Knechtel‭ · 2023-08-23T02:36:26Z (9 months ago)

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Use [`at`](https://en.wikipedia.org/wiki/At_%28command%29) to schedule the command, using `subprocess` from Python to invoke `at`. It doesn't even require `shell=True`. For example:
```
import subprocess
subprocess.run(
# `at` command to run now
"at now +10 minutes".split(),
# shell command that `at` will schedule, provided to `at`'s stdin
input="python -m this > this.txt",
# open stdin in text mode with the default encoding
text=True
)
```
Note that the `at` program will detach itself from the terminal, so capturing stdout or stderr from the scheduled task will require a workaround (such as invoking `xterm`, or `tee`ing to a TTY that will be open when the task runs).

Use [`at`](https://en.wikipedia.org/wiki/At_%28command%29) to schedule the command, using `subprocess` from Python to invoke `at`. It doesn't even require `shell=True`. For example:
```
import subprocess
subprocess.run(
# `at` command to run now
"at now +10 minutes".split(),
# shell command that `at` will schedule, provided to `at`'s stdin
input="python -m this > this.txt",
# open stdin in text mode with the default encoding
text=True
)
```
<section class="notice is-warning">
The `at` program will detach itself from the terminal, so capturing stdout or stderr from the scheduled task will require a workaround (such as invoking `xterm`, or `tee`ing to a TTY that will be open when the task runs).
However, if local mail services are available, and `at` is run from a `su` shell, it will send local mail with the output when the job is completed. Check the man page for details.
</section>

#1: Initial revision by

Karl Knechtel‭ · 2023-08-23T02:16:36Z (9 months ago)

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Use [`at`](https://en.wikipedia.org/wiki/At_%28command%29) to schedule the command, using `subprocess` from Python to invoke `at`. It doesn't even require `shell=True`. For example:

```
import subprocess

subprocess.run(
    # `at` command to run now
    "at now +10 minutes".split(),
    # shell command that `at` will schedule, provided to `at`'s stdin
    input="python -m this > this.txt",
    # open stdin in text mode with the default encoding
    text=True
)
```

Note that the `at` program will detach itself from the terminal, so capturing stdout or stderr from the scheduled task will require a workaround (such as invoking `xterm`, or `tee`ing to a TTY that will be open when the task runs).

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