Brackets, Braces, Curly Brackets in Bash
Here goes the riddle:
If I do:
touch file{1,2,3}
It creates file1, file2, file3
And if I do
rm file[1-3]
It deletes them.
but if I do
touch file[1-3]
it creates:
file[1-3]
Why?
bash syntax
edited Oct 14 '15 at 21:37
muru
1
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
add a comment |
Here goes the riddle:
If I do:
touch file{1,2,3}
It creates file1, file2, file3
And if I do
rm file[1-3]
It deletes them.
but if I do
touch file[1-3]
it creates:
file[1-3]
Why?
bash syntax
edited Oct 14 '15 at 21:37
muru
1
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
1
Try to repeat it doingshopt -s nullglobbefore - you'll understand it. See mywiki.wooledge.org/glob
– Rmano
Oct 14 '15 at 21:37
add a comment |
Here goes the riddle:
If I do:
touch file{1,2,3}
It creates file1, file2, file3
And if I do
rm file[1-3]
It deletes them.
but if I do
touch file[1-3]
it creates:
file[1-3]
Why?
bash syntax
edited Oct 14 '15 at 21:37
muru
1
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
Here goes the riddle:
If I do:
touch file{1,2,3}
It creates file1, file2, file3
And if I do
rm file[1-3]
It deletes them.
but if I do
touch file[1-3]
it creates:
file[1-3]
Why?
bash syntax
bash syntax
edited Oct 14 '15 at 21:37
muru
1
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
edited Oct 14 '15 at 21:37
muru
1
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
edited Oct 14 '15 at 21:37
muru
1
edited Oct 14 '15 at 21:37
muru
1
edited Oct 14 '15 at 21:37
muru
1
1
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
asked Oct 14 '15 at 21:24
UlukaiUlukai
220110
220110
1
Try to repeat it doingshopt -s nullglobbefore - you'll understand it. See mywiki.wooledge.org/glob
– Rmano
Oct 14 '15 at 21:37
add a comment |
1
Try to repeat it doingshopt -s nullglobbefore - you'll understand it. See mywiki.wooledge.org/glob
– Rmano
Oct 14 '15 at 21:37
1
1
Try to repeat it doing
shopt -s nullglob before - you'll understand it. See mywiki.wooledge.org/glob– Rmano
Oct 14 '15 at 21:37
Try to repeat it doing
shopt -s nullglob before - you'll understand it. See mywiki.wooledge.org/glob– Rmano
Oct 14 '15 at 21:37
add a comment |
1 Answer
1
active
oldest
votes
If you took the trouble of reading the manpage instead of making riddles:
Brace Expansion
Brace expansion is a mechanism by which arbitrary strings may be
generated. This mechanism is similar to pathname expansion, but the
filenames generated need not exist.
...
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 filenames matching the pattern (see
Pattern Matching below). If no matching filenames are found, and the
shell option nullglob is not enabled, the word is left unchanged.
...
Pattern Matching
Any character that appears in a pattern, other than the special pattern
characters described below, matches itself. ...
The special pattern characters have the following meanings:
...
[...] Matches any one of the enclosed characters. A pair of
characters separated by a hyphen denotes a range
expression; any character that falls between those two
characters, inclusive, using the current locale's
collating sequence and character set, is matched.
file[1-3] expands into files named file1, file2, file3. Filename expansion happens only if matching files exist. If not, the pattern is left as-is. Therefore, with files named file1, file2, file3, file[1-3] expands to file1 file2 file3. Without these files, it doesn't expand, and remains as file[1-3]. With {...}, the filenames don't have to exist, so file{1..3} expands to file1 file2 file3 irrespective of the files being present or absent.
answered Oct 14 '15 at 21:36
murumuru
1
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "89"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faskubuntu.com%2fquestions%2f685620%2fbrackets-braces-curly-brackets-in-bash%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
If you took the trouble of reading the manpage instead of making riddles:
Brace Expansion
Brace expansion is a mechanism by which arbitrary strings may be
generated. This mechanism is similar to pathname expansion, but the
filenames generated need not exist.
...
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 filenames matching the pattern (see
Pattern Matching below). If no matching filenames are found, and the
shell option nullglob is not enabled, the word is left unchanged.
...
Pattern Matching
Any character that appears in a pattern, other than the special pattern
characters described below, matches itself. ...
The special pattern characters have the following meanings:
...
[...] Matches any one of the enclosed characters. A pair of
characters separated by a hyphen denotes a range
expression; any character that falls between those two
characters, inclusive, using the current locale's
collating sequence and character set, is matched.
file[1-3] expands into files named file1, file2, file3. Filename expansion happens only if matching files exist. If not, the pattern is left as-is. Therefore, with files named file1, file2, file3, file[1-3] expands to file1 file2 file3. Without these files, it doesn't expand, and remains as file[1-3]. With {...}, the filenames don't have to exist, so file{1..3} expands to file1 file2 file3 irrespective of the files being present or absent.
answered Oct 14 '15 at 21:36
murumuru
1
add a comment |
If you took the trouble of reading the manpage instead of making riddles:
Brace Expansion
Brace expansion is a mechanism by which arbitrary strings may be
generated. This mechanism is similar to pathname expansion, but the
filenames generated need not exist.
...
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 filenames matching the pattern (see
Pattern Matching below). If no matching filenames are found, and the
shell option nullglob is not enabled, the word is left unchanged.
...
Pattern Matching
Any character that appears in a pattern, other than the special pattern
characters described below, matches itself. ...
The special pattern characters have the following meanings:
...
[...] Matches any one of the enclosed characters. A pair of
characters separated by a hyphen denotes a range
expression; any character that falls between those two
characters, inclusive, using the current locale's
collating sequence and character set, is matched.
file[1-3] expands into files named file1, file2, file3. Filename expansion happens only if matching files exist. If not, the pattern is left as-is. Therefore, with files named file1, file2, file3, file[1-3] expands to file1 file2 file3. Without these files, it doesn't expand, and remains as file[1-3]. With {...}, the filenames don't have to exist, so file{1..3} expands to file1 file2 file3 irrespective of the files being present or absent.
answered Oct 14 '15 at 21:36
murumuru
1
add a comment |
If you took the trouble of reading the manpage instead of making riddles:
Brace Expansion
Brace expansion is a mechanism by which arbitrary strings may be
generated. This mechanism is similar to pathname expansion, but the
filenames generated need not exist.
...
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 filenames matching the pattern (see
Pattern Matching below). If no matching filenames are found, and the
shell option nullglob is not enabled, the word is left unchanged.
...
Pattern Matching
Any character that appears in a pattern, other than the special pattern
characters described below, matches itself. ...
The special pattern characters have the following meanings:
...
[...] Matches any one of the enclosed characters. A pair of
characters separated by a hyphen denotes a range
expression; any character that falls between those two
characters, inclusive, using the current locale's
collating sequence and character set, is matched.
file[1-3] expands into files named file1, file2, file3. Filename expansion happens only if matching files exist. If not, the pattern is left as-is. Therefore, with files named file1, file2, file3, file[1-3] expands to file1 file2 file3. Without these files, it doesn't expand, and remains as file[1-3]. With {...}, the filenames don't have to exist, so file{1..3} expands to file1 file2 file3 irrespective of the files being present or absent.
answered Oct 14 '15 at 21:36
murumuru
1
If you took the trouble of reading the manpage instead of making riddles:
Brace Expansion
Brace expansion is a mechanism by which arbitrary strings may be
generated. This mechanism is similar to pathname expansion, but the
filenames generated need not exist.
...
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 filenames matching the pattern (see
Pattern Matching below). If no matching filenames are found, and the
shell option nullglob is not enabled, the word is left unchanged.
...
Pattern Matching
Any character that appears in a pattern, other than the special pattern
characters described below, matches itself. ...
The special pattern characters have the following meanings:
...
[...] Matches any one of the enclosed characters. A pair of
characters separated by a hyphen denotes a range
expression; any character that falls between those two
characters, inclusive, using the current locale's
collating sequence and character set, is matched.
file[1-3] expands into files named file1, file2, file3. Filename expansion happens only if matching files exist. If not, the pattern is left as-is. Therefore, with files named file1, file2, file3, file[1-3] expands to file1 file2 file3. Without these files, it doesn't expand, and remains as file[1-3]. With {...}, the filenames don't have to exist, so file{1..3} expands to file1 file2 file3 irrespective of the files being present or absent.
answered Oct 14 '15 at 21:36
murumuru
1
edited Oct 14 '15 at 21:42
answered Oct 14 '15 at 21:36
murumuru
1
answered Oct 14 '15 at 21:36
murumuru
1
answered Oct 14 '15 at 21:36
murumuru
1
1
add a comment |
add a comment |
Thanks for contributing an answer to Ask Ubuntu!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2faskubuntu.com%2fquestions%2f685620%2fbrackets-braces-curly-brackets-in-bash%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
1
Try to repeat it doing
shopt -s nullglobbefore - you'll understand it. See mywiki.wooledge.org/glob– Rmano
Oct 14 '15 at 21:37