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launch bash without using any letters

Terminal - launch bash without using any letters
$0
2013-03-05 22:57:14
User: fhtagn
0
launch bash without using any letters

Starts a new shell (in bash/sh, it starts bash/sh). 'man bash' explains:

"If arguments remain after option processing, and neither the -c nor the -s option has been supplied, the first argument is assumed to be the name of a file containing shell commands. If bash is invoked in this fashion, $0 is set to the name of the file, and the positional parameters are set to the remaining arguments."

Alternatives

There are 4 alternatives - vote for the best!

Terminal - Alternatives
${0/-/}
2012-12-31 17:43:08
User: ry4an
7

ry4an@four:~$ echo $SHLVL

1

ry4an@four:~$ ${0/-/}

ry4an@four:~$ echo $SHLVL

2

"$(- 2>&1)";${_%%:*}
2012-12-29 09:21:09
User: LinuxMan
6

I don't know why anyone would use this, I was just messing around tonight and managed to start bash without using any letters and thought I would share. It's pretty simple, first it tries to execute "-" redirecting stderr to stdout which prints the error "bash: -: command not found" to standard output, then I try to execute "bash: -: command not found" which produces the output "bash: bash: -: command not found: command not found". lastly, (on the other side of the semicolon) I use the underscore environment variable which refers to the last command run ("bash: -: command not found") and take out everything after the first ":" character using brace expressions and your left with "bash"

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