mirror of
https://github.com/notwa/rc
synced 2024-11-05 06:39:02 -08:00
30 lines
869 B
Bash
Executable file
30 lines
869 B
Bash
Executable file
#!/usr/bin/env sh
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# YES_ZSH YES_BASH YES_DASH YES_ASH
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bak() { ### @-
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### backup files by creating copies and appending ".bak" to their names.
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### this calls itself recursively to avoid clobbering existing backups.
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###
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### ```
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### $ touch -d '2001-12-25 16:30:00' butts
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### $ bak butts
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### $ touch butts
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### $ bak butts
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### $ ls -l
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### total 0
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### -rw-r--r-- 1 notwa None 0 Aug 1 08:02 butts
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### -rw-r--r-- 1 notwa None 0 Aug 1 08:02 butts.bak
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### -rw-r--r-- 1 notwa None 0 Dec 25 2001 butts.bak.bak
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### ```
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[ $# -gt 0 ] || { printf "%s\n" "$0: too few arguments" >&2; return 1; }
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local ret=0 f=
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for f; do
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if [ -e "$f.bak" ]; then
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bak "$f.bak" || { ret=1; continue; }
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fi
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cp -p "$f" "$f.bak" || ret=1
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done
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return $ret
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}
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[ -n "${preload+-}" ] || bak "$@"
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