mirror of
https://github.com/topjohnwu/ndk-busybox.git
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90 lines
1.9 KiB
Plaintext
90 lines
1.9 KiB
Plaintext
# try running this with bash, ksh, ash, and hush.
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# simple quoting rules.
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echo a b
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echo "a b"
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echo a "" b
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echo a '' b
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echo hello?
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echo "hello?"
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echo t* hello
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echo t\* hello
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# quick and painless exit for lash
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if false; then true; exit; fi
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# fairly simple command substitution
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echo `echo -e foo\\\necho bar`
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echo THIS IS A TEST >foo
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cat $(echo FOO | tr 'A-Z' 'a-z')
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cat foo | tr 'A-Z' 'a-z'
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cat $(echo FOO | tr 'A-Z' 'a-z') | tr 'A-Z' 'a-z'
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cat foo | if true; then tr 'A-Z' 'a-z'; else echo bar1; fi
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cat foo | if false; then tr 'A-Z' 'a-z'; else echo bar2; fi
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if true; then tr 'A-Z' 'a-z'; else echo bar3; fi <foo
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if false; then tr 'A-Z' 'a-z'; else echo bar4; fi <foo
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if true || false; then echo foo; else echo bar5; fi
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if true && false; then echo bar6; else echo foo; fi
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# basic distinction between local and env variables
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unset FOO
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FOO=bar env | grep FOO
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echo "but not here: $FOO"
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FOO=bar
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env | grep FOO
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echo "yes, here: $FOO"
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FOO=
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echo a $FOO b
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echo "a $FOO b"
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# not quite so basic variables. Credit to Matt Kraai.
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unset FOO
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FOO=bar
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export FOO
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env | grep FOO
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unset FOO
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export FOO=bar
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FOO=baz
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env | grep FOO
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# interaction between environment variables and if/then and subshells
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FOO=default
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if true; then FOO=new; fi
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echo $FOO
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FOO=default
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(FOO=bogus)
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echo $FOO
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# make sure we can duplicate file descriptors properly
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echo replacement >foo 2>&1
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cat foo
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cat doesnt_exist >foo 2>&1
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tr 'a-z' 'A-Z' <foo
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# fairly simple example of hush expanding variables too early
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unset TMP
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rm -f fish
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TMP=fish && >$TMP
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ls fish
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# ash, lash, and hush do not create wish; bash and ksh do.
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# Thanks to Tapani Tarvainen <tt@mit.jyu.fi> for this stress test.
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unset TMP
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rm -f wish
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TMP=wish >$TMP
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ls wish
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# The following example shows that hush's parser is
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# not _really_ Bourne compatible
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echo "echo Hello World" >"a=b"
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unset a
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chmod a+x "a=b"
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PATH=$PATH:.
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"a=b"
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echo $a
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# assuming the shell wasn't too buggy, clean up the mess
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rm -f a=b wish fish foo
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