BASH File Expansion

[verbal_666]

Hi.
A stupid, maybe , question:

HOW can i prevent BASH to expand FileSystem integration when using special chars inside a command?

I mean, having the /tmp looks like this,

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/tmp
├── dir
│   └── test2
└── test

Now, i want to simply apply a for cycle with my strings, without having them expanded to FileSystem,

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s="/tmp/* /tmp/dir/*"
for f in $s;do echo "$f";done

OUTPUT:
/tmp/dir
/tmp/test
/tmp/dir/test2

The for command expands my string to a FileSystem expanded object!!!


What i need is a simple,

OUTPUT:
/tmp/*
/tmp/dir/*

The only way i found is to trick the system and add a "pattern" to exlude FileSystem expansion,

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s="^/tmp/* ^/tmp/dir/*"
for f in $s;do echo "${f/^/}";done

And i get my OUTPUT:
/tmp/*
/tmp/dir/*

Is there another way, OS/Bash level, to make this expansion disabled?
Thanks.

[TrevorH]

Try

s="/tmp/\* /tmp/dir/\*"

[jlehtone]

The '\' appears in output, at least on interactive command.
(One must remember that a typed command and a command in script can expand differently.)

man bash (and more clearly info bash) says in section "Path expansion"
that if '-f' is set, then globbing does not occur. Hence:

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set -f ; for f in $s ; do echo $f ; done ; set +f

[owl102]

An alternative would be using an bash array:

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s=( "/tmp/*" "tmp/dir/*" )
for f in "${s[@]}";do echo "$f";done

[verbal_666]

man bash (and more clearly info bash) says in section "Path expansion"
that if '-f' is set, then globbing does not occur. Hence:

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set -f ; for f in $s ; do echo $f ; done ; set +f

GREEEEEEEEEEEEEEEEAT!!! That is what i was looking for!!! I read the man bash, but really didn't find!!! My fault. HERE IT IS!!!

Pathname Expansion
After word splitting, unless the -f option has been set, bash scans each word for the characters *, ?, and [. If one of these characters appears, then the word is regarded as a pattern,and replaced with an alphabetically sorted list of file names matching the pattern. If no matching file names are found, and the shell option nullglob is not enabled, the word is left unchanged. If the nullglob option is set, and no matches are found, the word is removed. If the failglob shell option is set, and no matches are found, an error message is printed and the command is not executed. If the shell option nocaseglob is enabled, the match is performed without regard to the case of alphabetic characters. When a pattern is used for pathname expansion, the character ``.'' at the start of a name or immediately following a slash must be matched explicitly, unless the shell option dotglob is set. When matching a pathname, the slash character must always be matched explicitly. In other cases, the ``.'' character is not treated specially. See the description of shopt below under SHELL BUILTIN COMMANDS for a description of the nocaseglob, nullglob, failglob, and dotglob shell options.

Really thanks!!!