Florian WaltherandClaude Opus 5.5
1f507f6562
- ${#v}, ${v#p} ${v##p} ${v%p} ${v%%p}, ${v/p/r} ${v//p/r} ${v/#p/r}
${v/%p/r}, ${v:off:len}, ${v-w} ${v:=w} ${v:+w} ${v:?msg}; nested ${}
- arithmetic expansion $((...)) with the C operators, ** and assignments
- set -e, set -x, set -o pipefail (also as gosh options, passed on to
subshells); set shows variables, set -o the options
- trap for EXIT and signals; scripts with an EXIT trap run it on
SIGINT/SIGTERM/SIGHUP too
- eval, exec (also exec > file without a command), $!, wait pid
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
17 lines
298 B
Go
17 lines
298 B
Go
package main
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import (
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"os"
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"golang.org/x/sys/unix"
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)
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// dupTo makes file descriptor fd refer to f (dup2; linux/arm64 only has
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// dup3).
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func dupTo(f *os.File, fd int) error {
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if int(f.Fd()) == fd {
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return nil // dup3 fails for the same descriptor
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}
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return unix.Dup3(int(f.Fd()), fd, 0)
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}
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