fzy-tmux: fix escaping#203
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The exit code returned by fzy-tmux is the exit status of the "cut" command that's run before "tmux" rather than the exit status of "fzy". This is because "$?" is not escaped. To get the exit status of "fzy" we need to escape it twice, once to prevent parameter expansion inside the double quotes and again to prevent expansion by eval. The arguments passed to fzy-tmux are expanded, then the expanded arguments are evaluated by "eval" and then the result of that is evaluated by the shell running inside tmux. Evaluating them multiple times can lead to surprising behavior as the argument values are subject to parameter expansion and command substitution. By escaping "$*" we prevent the arguments from being expanded before they are passed to "eval". Ideally we'd also prevent "eval" from expanding them as well so that they were evaluated only in the shell running inside tmux but there isn't a simple way to do that and adding one level of escaping does at least remove one level of unwanted expansion.
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I'm not really sure why it is using |
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The exit code returned by fzy-tmux is the exit status of the "cut" command that's run before "tmux" rather than the exit status of "fzy". This is because "$?" is not escaped. To get the exit status of "fzy" we need to escape it twice, once to prevent parameter expansion inside the double quotes and again to prevent expansion by eval.
The arguments passed to fzy-tmux are expanded, then the expanded arguments are evaluated by "eval" and then the result of that is evaluated by the shell running inside tmux. Evaluating them multiple times can lead to surprising behavior as the argument values are subject to parameter expansion and command substitution. By escaping "$*" we prevent the arguments from being expanded before they are passed to "eval". Ideally we'd also prevent "eval" from expanding them as well so that they were evaluated only in the shell running inside tmux but there isn't a simple way to do that and adding one level of escaping does at least remove one level of unwanted expansion.