docs(cli): correct the stated cause of a bootstrap that never returns - #1183
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I wrote that source is a POSIX special builtin and that a syntax error in the sourced file therefore terminates the shell. Measured, that is wrong: set +e, syntax error source returns 1, execution continues set -e, syntax error shell exits (2) set +e, bare exit 3 shell exits (3) So the two modes have different causes. A syntax error makes source return non-zero like any other command, and the shell only dies because set -e is active at that point. A bare exit ends the shell regardless. The marker and EXIT trap still cover both and stay fork-free, but the alternative I dismissed -- set +e around the source, then check the status -- would have caught the syntax-error case; it just would not catch a bare exit. The conclusion held, the reasoning did not. Comments only; no behaviour change. Corrections also posted on #1179 and #1181.
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🤔 Background
#1179 and #1181 state that
sourceis a POSIX special builtin and that a syntaxerror therefore terminates the shell. Measured, that is wrong:
set +e, syntax errorsourcereturns 1, execution continuesset -e, syntax errorset +e, bareexit 3A syntax error makes
sourcereturn non-zero like any other command; the shellonly dies because
set -eis active at that point. A bareexitends itregardless.
💡 Changes
set +e, source, check status) would have caught the syntax-error case; it just would not catch a bareexit. The conclusion held, the reasoning did not