Fix style #5648
Fix style #5648
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Sorry, didn't realize we were style checking under |
etc/bin/swarm
Outdated
| @@ -204,7 +204,7 @@ append_config () { | |||
| if prompt "Write \"$LINE\" to \"$LOC\"?"; then | |||
| if [[ "$POS" == top ]]; then | |||
| # ... at the top of the file | |||
| echo -e "${LINE}\n$(cat ${LOC})" > "$LOC" | |||
| echo -e "${LINE}\n$(cat "$LOC")" > temp && mv temp "$LOC" | |||
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I get the quoting, but is the temp file necessary?
cat foo > foo wipes out foo, but the echo here makes it safe. (I confess I'm unsure of exactly why though!)
[Update]
In cat foo > foo, the file foo is opened in truncation mode before the command is executed, ready to receive the output of the command, so the content is lost.
In echo -e "$(cat foo)" > foo, the command substitution is done first (because it is used to construct the final command) before the file is opened in truncation mode, so this is safe.
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Funny, shellcheck was complaining about SC2094 locally
Make sure not to read and write the same file in the same pipeline
But apparently not on GH Actions?
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Ah OK, my local shellcheck must be outdated, didn't see that. However, going by my logic above, SC2094 should not apply for this particular construct.
Follow-up to #5639