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Large list of changes, including formatting and typos for most commands. More substantive changes have been made to alias, bind, block, break, builtin, case, cd, commandline, count, else, emit, fish_config, funced, function, functions, history, math, mimedb, nextd, not, popd, prevd, pushd, pwd, random, read, set, set_color, switch, test, trap, type, ulimit, umask, and while.
44 lines
1.7 KiB
Plaintext
44 lines
1.7 KiB
Plaintext
\section trap trap - perform an action when the shell receives a signal
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\subsection trap-synopsis Synopsis
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<tt>trap [OPTIONS] [[ARG] SIGSPEC ... ]</tt>
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\subsection trap-description Description
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\c trap is a wrapper around the fish event delivery
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framework. It exists for backwards compatibility with POSIX
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shells. For other uses, it is recommended to define an <a
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href='index.html#event'>event handler</a>.
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The following parameters are available:
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- \c ARG is the command to be executed on signal delivery.
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- \c SIGSPEC is the name of the signal to trap.
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- \c -h or \c --help displays help and exits.
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- \c -l or \c --list-signals prints a list of signal names.
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- \c -p or \c --print prints all defined signal handlers.
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If \c ARG and \c SIGSPEC are both specified, \c ARG is the command to be
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executed when the signal specified by \c SIGSPEC is delivered.
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If \c ARG is absent (and there is a single SIGSPEC) or -, each specified
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signal is reset to its original disposition (the value it had upon
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entrance to the shell). If \c ARG is the null string the signal
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specified by each \c SIGSPEC is ignored by the shell and by the commands
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it invokes.
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If \c ARG is not present and \c -p has been supplied, then the trap commands
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associated with each \c SIGSPEC are displayed. If no arguments are
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supplied or if only \c -p is given, \c trap prints the list of commands
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associated with each signal.
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Signal names are case insensitive and the \c SIG prefix is optional.
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The return status is 1 if any \c SIGSPEC is invalid; otherwise trap
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returns 0.
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\subsection trap-example Example
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<code>trap "status --print-stack-trace" SIGUSR1</code> prints a stack trace
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each time the \c SIGUSR1 signal is sent to the shell.
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