Creating a file in a folder - io

How do I create a file in a certain folder in Rust?
I have tried the following approaches:
let f = File::create(Path::new(format!("{}{}","/files/",filename).as_str()));
let f = File::create(format!("{}{}","/files/",filename));
Both result in:
The system cannot find the path specified. (os error 3)
I have managed to create the file in the same directory as the executable with:
let f = File::create(format!("{}",filename));
So how do I go about creating files in a specific directory?
ls on basefolder:
PS C:\trust\svd2rust\target\debug> ls
Directory: C:\trust\svd2rust\target\debug
Mode LastWriteTime Length Name
---- ------------- ------ ----
d----- 2017-01-24 12:13 .fingerprint
d----- 2017-01-24 12:13 build
d----- 2017-01-26 10:06 deps
d----- 2017-01-24 12:13 examples
d----- 2017-01-26 07:18 files
d----- 2017-01-24 12:13 incremental
d----- 2017-01-24 12:13 native
-a---- 2017-01-24 12:13 0 .cargo-lock
-a---- 2017-01-26 10:06 1079240 libsvd2rust.rlib
-a---- 2017-01-24 21:08 27608 log.rs
-a---- 2017-01-24 13:55 27372 log2.rs
-a---- 2016-08-23 15:07 565888 STM32F401x.svd
-a---- 2016-08-23 15:07 912360 STM32F401xE.svd
-a---- 2016-08-23 15:07 1907985 STM32F40x.svd
-a---- 2017-01-26 10:06 11761561 svd2rust.exe

Using "files/" instead of "/files/" solved the problem.
It seems "/files/" references to the absolute path of C:\files, while "files/" references to the relative path of the executable.
So when using "/files/" it did't work since there was no folder C:\Files.

Related

configparser can't read regular config file, no section

configparser (Python 3.7) found no section in regular config file
I don't get why this code won't work, I checked every detail in the doc. What can be wrong with my cnf file format?
File /home/julien/Workspace/BnsManager/data/.secret/.paris.cnf
[ldap]
admin_dn=Directory Manager
admin_password=superpassword
Permissions on .secret folder
ls -la .secret/
drwxrwxr-x 2 julien julien 4096 oct. 16 15:51 .
drwxrwxr-x 6 julien julien 4096 oct. 16 15:42 ..
-rw-rw-r-- 1 julien julien 60 oct. 17 08:48 .paris.cnf
File test.py
import configparser
p = '/home/julien/Workspace/BnsManager/data/.secret/.paris.cnf'
cp = configparser.ConfigParser()
cp.read(p)
print(cp.sections())
The ouput is [] but I expected it to be ['ldap']
Do you see what went wrong?
Try this to get the exception with explanation why the file is not read:
import configparser
p = '/home/julien/Workspace/BnsManager/data/.secret/.paris.cnf'
with open(p, 'r'):
print('file could be opened')
cp = configparser.ConfigParser()
cp.read(p)
print(cp.sections())

why there is a "node_module" folder in #uirouter/angular/?

I have a angularjs1.6.7 app depending on below lib:
"#uirouter/angular": "^1.0.1",
"#uirouter/angular-hybrid": "^3.1.10",
"#uirouter/angularjs": "^1.0.15",
"#uirouter/core": "^5.0.17",
"#uirouter/rx": "^0.4.5",
when I run command "npm run build" , it generates node_module like below:
E:\20-work\06-svn\datarein\01-Dev\branches\dev\datarein\ui\ui-app\node_modules\#uirouter\angular
2019/10/10 14:47 <DIR> .
2019/10/10 14:47 <DIR> ..
2017/08/13 10:43 71 artifacts.json
2018/05/03 12:24 117,843 CHANGELOG.md
2017/04/23 05:53 3,982 CONTRIBUTING.md
2018/01/02 03:12 266 downstream_projects.json
2018/03/28 04:56 1,677 karma.conf.js
2019/10/10 14:44 <DIR> lib
2017/04/05 11:42 1,102 LICENSE
2019/10/10 14:47 <DIR> node_modules
2019/10/10 14:47 4,031 package.json
2017/12/27 09:15 1,750 README.md
2018/04/20 09:35 886 typedoc.json
2019/10/10 14:44 <DIR> _bundles
and in the above "angular/node_modules" there is another #uirouter/core folder :
E:\20-work\06-svn\datarein\01-Dev\branches\dev\datarein\ui\ui-app\node_modules\#uirouter\angular\node_modules\#uirouter\core>dir
2019/10/10 14:47 <DIR> .
2019/10/10 14:47 <DIR> ..
2018/02/08 08:26 86 artifacts.json
2018/04/30 06:58 102,786 CHANGELOG.md
2017/09/21 11:11 3,771 CONTRIBUTING.md
2018/02/08 08:27 459 downstream_projects.json
2019/10/10 14:45 <DIR> lib
2019/10/10 14:44 <DIR> lib-esm
2017/09/21 11:11 1,102 LICENSE
2019/10/10 14:47 4,147 package.json
2018/02/08 08:27 3,261 README.md
2018/04/30 02:18 804 typedoc.json
2019/10/10 14:44 <DIR> _bundles
I am guessing it cause below error
error TS2345: Argument of type 'StateDeclaration' is not assignable to parameter of type 'StateOrName'.
Type 'import("/ui-app/node_modules/#uirouter/core/lib/state/interface").StateDeclaration' is not assignable to type 'import("/ui-app/node_modules/#uirouter/angular/node_modules/#uirouter/core/lib/state/interface").StateDeclaration'.
Types of property 'parent' are incompatible.
Would someone help to advise?
env spec:
windows10,
node 6.4.1
angularjs 1.6.7

How to check if a locale is UTF-8?

I'm working with Yocto to create an embedded linux distribution for an ARM device (i.MX 6Quad Processors).
I've configured the list of desired locales with the variable:
IMAGE_LINGUAS = "de-de fr-fr en-gb en-gb.iso-8859-1 en-us en-us.iso-8859-1 zh-cn"
As result I've obtained a file systems that contains the following folders:
root#lam_icu:/usr/lib/locale# cd /usr/share/locale/
root#lam_icu:/usr/share/locale# ls -la
total 0
drwxr-xr-x 6 root root 416 Nov 17 2016 .
drwxr-xr-x 30 root root 2056 Nov 17 2016 ..
drwxr-xr-x 4 root root 296 Nov 17 2016 de
drwxr-xr-x 3 root root 232 Nov 17 2016 en_GB
drwxr-xr-x 4 root root 296 Nov 17 2016 fr
drwxr-xr-x 4 root root 296 Nov 17 2016 zh_CN
and:
root#lam_icu:/usr/share/locale# cd /usr/lib/locale/
root#lam_icu:/usr/lib/locale# ls -la
total 0
drwxr-xr-x 9 root root 640 Mar 13 2017 .
drwxr-xr-x 32 root root 40000 Mar 13 2017 ..
drwxr-xr-x 3 root root 1016 Mar 13 2017 de_DE
drwxr-xr-x 3 root root 1016 Mar 13 2017 en_GB
drwxr-xr-x 3 root root 1016 Mar 13 2017 en_GB.ISO-8859-1
drwxr-xr-x 3 root root 1016 Mar 13 2017 en_US
drwxr-xr-x 3 root root 1016 Mar 13 2017 en_US.ISO-8859-1
drwxr-xr-x 3 root root 1016 Mar 13 2017 fr_FR
drwxr-xr-x 3 root root 1016 Mar 13 2017 zh_CN
Which is the encoding of all non ISO-8859-1 locales? Can I assume that "en_GB" or "en_US" use the UTF-8 encoding?
I've tried to open the "LC_IDENTIFICATION" file, the result is:
Hc�������������cEnglish locale for the USAFree Software
Foundation,
Inc.http://www.gnu.org/software/libc/bug-glibc-locales#gnu.orgEnglishUSA1.02000-06-24en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000en_US:2000UTF-8
At the end of the file there is something that recalls "UTF-8". Is this enough to assume that the encoding is UTF-8?
How to check if a locale is UTF-8?
LC_IDENTIFICATION doesn't tell you much:
LC_IDENTIFICATION - this is not a user-visible category, it contains information about the locale itself and is rarely useful for users or developers (but is listed here for completeness sake).
You'd have to look at the complete set of files.
There appears to be no standard command-line utility for doing this, but there is a runtime call (added a little later than the original locale functions). Here is a sample program which illustrates the function nl_langinfo:
#include <stdio.h>
#include <locale.h>
#include <langinfo.h>
int
main(int argc, char **argv)
{
int n;
for (n = 1; n < argc; ++n) {
if (setlocale(LC_ALL, argv[n]) != 0) {
char *code = nl_langinfo(CODESET);
if (code != 0)
printf("%s ->%s\n", argv[n], code);
else
printf("?%s (nl_langinfo)\n", argv[n]);
} else {
printf("? %s (setlocale)\n", argv[n]);
}
}
return 0;
}
and some output, e.g., by foo $(locale -a):
aa_DJ ->ISO-8859-1
aa_DJ.iso88591 ->ISO-8859-1
aa_DJ.utf8 ->UTF-8
aa_ER ->UTF-8
aa_ER#saaho ->UTF-8
aa_ER.utf8 ->UTF-8
aa_ER.utf8#saaho ->UTF-8
aa_ET ->UTF-8
aa_ET.utf8 ->UTF-8
af_ZA ->ISO-8859-1
af_ZA.iso88591 ->ISO-8859-1
af_ZA.utf8 ->UTF-8
am_ET ->UTF-8
am_ET.utf8 ->UTF-8
an_ES ->ISO-8859-15
an_ES.iso885915 ->ISO-8859-15
an_ES.utf8 ->UTF-8
ar_AE ->ISO-8859-6
ar_AE.iso88596 ->ISO-8859-6
ar_AE.utf8 ->UTF-8
ar_BH ->ISO-8859-6
ar_BH.iso88596 ->ISO-8859-6
The directory names you're referring to are often (but not required) to be the same as encoding names. That is the assumption made in the example program. There was a related question in How to get terminal's Character Encoding, but it has no useful answers. One is interesting though, since it asserts that
locale charmap
will give the locale encoding. According to the standard, that's not necessarily so:
The command locale charmap gives the name used in localedef -f
However, localedef attaches no special meaning to the name given in the -f option.
localedef has a different option -u which identifies the codeset, but locale (in the standard) mentions no method for displaying this information.
As usual, implementations may (or may not) treat unspecified features in different ways. The GNU C library's documentation differs in some respects from the standard (see locale and localedef), but offers no explicit options for showing the codeset name.

OCaml error: Unbound module Event

I try to build a short ocaml event example. But when I compile, the error in the title appears.
The question of: unbound module Event error when compiling Ocaml game was not helpful for me.
The system is Kubuntu 14.04 and I installed ocaml over aptitude, so installed packages are:
camlp4, ledit, libfindlib-ocaml, libfindlib-ocaml-dev, liboasis-ocaml, liboasis-ocaml-dev, libodn-ocaml, libodn-ocaml-dev, libtype-conv-camlp4-dev, oasis, ocaml, ocaml-base, ocaml-base-nox, ocaml-compiler-libs, ocaml-doc, ocaml-findlib, ocaml-interp, ocaml-native-compilers, ocaml-nox
The OCaml compiler is version 4.01.0
Here is my short test program.
open Thread;;
open Event;;
let chan = Event.new_channel();;
let a () =
Printf.printf "A waiting...\n";;
let sigRX = Event.receive chan in
Printf.printf "A received over channel\n";
let v = Event.sync sigRx in
Printf.printf "A running\n";
Printf.printf "A done!\n";;
let b () =
Thread.delay 0.8
Printf.printf "B sending...\n";;
let sigTX = Event.send "wake up" in
Event.sync sigTX;
Printf.printf "B done!\n";;
let t_a = Thread.create a ();;
let t_b = Thread.create b ();;
I tried to compile this single file (test.ml) with:
ocamlc -thread unix.cma threads.cma test.ml
The response is:
File "test.ml", line 2, characters 0-10:
Error: Unbound module Event
I googled, found some "thread-using-tips" like: http://caml.inria.fr/pub/docs/manual-ocaml/libthreads.html#c%3Athreads
In /usr/lib/ocaml is an threads folder and an thread.mli. Inside the threads folder there are this files:
-rw-r--r-- 1 root root 487 Jan 2 2014 condition.cmi
-rw-r--r-- 1 root root 487 Jan 2 2014 condition.cmx
-rw-r--r-- 1 root root 1203 Jan 2 2014 event.cmi
-rw-r--r-- 1 root root 1867 Jan 2 2014 event.cmx
-rw-r--r-- 1 root root 421 Jan 2 2014 mutex.cmi
-rw-r--r-- 1 root root 407 Jan 2 2014 mutex.cmx
-rw-r--r-- 1 root root 1859 Jan 2 2014 thread.cmi
-rw-r--r-- 1 root root 1308 Jan 2 2014 thread.cmx
-rw-r--r-- 1 root root 62778 Jan 2 2014 threads.a
-rw-r--r-- 1 root root 47047 Jan 2 2014 threads.cma
-rw-r--r-- 1 root root 1258 Jan 2 2014 threads.cmxa
-rw-r--r-- 1 root root 4145 Jan 2 2014 threadUnix.cmi
-rw-r--r-- 1 root root 1515 Jan 2 2014 threadUnix.cmx
What am I missing? I assume, that the Event is packed in Thread Module?
This command line works for me to get past the unbound module problem.
$ ocamlc -I +threads -c test.ml
There are errors in your code, but I imagine you'll know how to fix them.
This full command line will probably work, but I can't be sure because of the errors:
$ ocamlc -thread -I +threads unix.cma threads.cma test.ml
(There are some higher-level tools for building OCaml programs that you might want to learn about at some point.)

How to get file creation date/time in Bash/Debian?

I'm using Bash on Debian GNU/Linux 6.0. Is it possible to get the file creation date/time? Not the modification date/time.
ls -lh a.txt and stat -c %y a.txt both only give the modification time.
Unfortunately your quest won't be possible in general, as there are only 3 distinct time values stored for each of your files as defined by the POSIX standard (see Base Definitions section 4.8 File Times Update)
Each file has three distinct associated timestamps: the time of last
data access, the time of last data modification, and the time the file
status last changed. These values are returned in the file
characteristics structure struct stat, as described in <sys/stat.h>.
EDIT: As mentioned in the comments below, depending on the filesystem used metadata may contain file creation date. Note however storage of information like that is non standard. Depending on it may lead to portability problems moving to another filesystem, in case the one actually used somehow stores it anyways.
ls -i file #output is for me 68551981
debugfs -R 'stat <68551981>' /dev/sda3 # /dev/sda3 is the disk on which the file exists
#results - crtime value
[root#loft9156 ~]# debugfs -R 'stat <68551981>' /dev/sda3
debugfs 1.41.12 (17-May-2010)
Inode: 68551981 Type: regular Mode: 0644 Flags: 0x80000
Generation: 769802755 Version: 0x00000000:00000001
User: 0 Group: 0 Size: 38973440
File ACL: 0 Directory ACL: 0
Links: 1 Blockcount: 76128
Fragment: Address: 0 Number: 0 Size: 0
ctime: 0x526931d7:1697cce0 -- Thu Oct 24 16:42:31 2013
atime: 0x52691f4d:7694eda4 -- Thu Oct 24 15:23:25 2013
mtime: 0x526931d7:1697cce0 -- Thu Oct 24 16:42:31 2013
**crtime: 0x52691f4d:7694eda4 -- Thu Oct 24 15:23:25 2013**
Size of extra inode fields: 28
EXTENTS:
(0-511): 352633728-352634239, (512-1023): 352634368-352634879, (1024-2047): 288392192-288393215, (2048-4095): 355803136-355805183, (4096-6143): 357941248-357943295, (6144
-9514): 357961728-357965098
mikyra's answer is good. The fact just like what he said.
[jason#rh5 test]$ stat test.txt
File: `test.txt'
Size: 0 Blocks: 8 IO Block: 4096 regular empty file
Device: 802h/2050d Inode: 588720 Links: 1
Access: (0664/-rw-rw-r--) Uid: ( 500/ jason) Gid: ( 500/ jason)
Access: 2013-03-14 01:58:12.000000000 -0700
Modify: 2013-03-14 01:58:12.000000000 -0700
Change: 2013-03-14 01:58:12.000000000 -0700
if you want to verify, which file was created first, you can structure your file name by appending system date when you create a series of files.
Note that if you've got your filesystem mounted with noatime for performance reasons, then the atime will likely show the creation time. Given that noatime results in a massive performance boost (by removing a disk write for every time a file is read), it may be a sensible configuration option that also gives you the results you want.
Creation date/time is normally not stored. So no, you can't.
You can find creation time - aka birth time - using stat and also match using find.
We have these files showing last modified time:
$ ls -l --time-style=long-iso | sort -k6
total 692
-rwxrwx---+ 1 XXXX XXXX 249159 2013-05-31 14:47 Getting Started.pdf
-rwxrwx---+ 1 XXXX XXXX 275799 2013-12-30 21:12 TheScienceofGettingRich.pdf
-rwxrwx---+ 1 XXXX XXXX 25600 2015-05-07 18:52 Thumbs.db
-rwxrwx---+ 1 XXXX XXXX 148051 2015-05-07 18:55 AsAManThinketh.pdf
To find files created within a certain time frame using find as below.
Clearly, the filesystem knows about the birth time of a file:
$ find -newerBt '2014-06-13' ! -newerBt '2014-06-13 12:16:10' -ls
20547673299906851 148 -rwxrwx--- 1 XXXX XXXX 148051 May 7 18:55 ./AsAManThinketh.pdf
1407374883582246 244 -rwxrwx--- 1 XXXX XXXX 249159 May 31 2013 ./Getting\ Started.pdf
We can confirm this using stat:
$ stat -c "%w %n" * | sort
2014-06-13 12:16:03.873778400 +0100 AsAManThinketh.pdf
2014-06-13 12:16:04.006872500 +0100 Getting Started.pdf
2014-06-13 12:16:29.607075500 +0100 TheScienceofGettingRich.pdf
2015-05-07 18:32:26.938446200 +0100 Thumbs.db
stat man pages explains %w:
%w time of file birth, human-readable; - if unknown
ls -i menus.xml
94490 menus.xml
Here the number 94490 represents inode
Then do a:
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg-root 4.0G 3.4G 408M 90% /
tmpfs 1.9G 0 1.9G 0% /dev/shm
/dev/sda1 124M 27M 92M 23% /boot
/dev/mapper/vg-var 7.9G 1.1G 6.5G 15% /var
To find the mounting point of the root "/" filesystem, because the file menus.xml is on '/' that is '/dev/mapper/vg-root'
debugfs -R 'stat <94490>' /dev/mapper/vg-root
The output may be like the one below:
debugfs -R 'stat <94490>' /dev/mapper/vg-root
debugfs 1.41.12 (17-May-2010)
Inode: 94490 Type: regular Mode: 0644 Flags: 0x0
Generation: 2826123170 Version: 0x00000000
User: 0 Group: 0 Size: 4441
File ACL: 0 Directory ACL: 0
Links: 1 Blockcount: 16
Fragment: Address: 0 Number: 0 Size: 0
ctime: 0x5266e438 -- Wed Oct 23 09:46:48 2013
atime: 0x5266e47b -- Wed Oct 23 09:47:55 2013
mtime: 0x5266e438 -- Wed Oct 23 09:46:48 2013
Size of extra inode fields: 4
Extended attributes stored in inode body:
selinux = "unconfined_u:object_r:usr_t:s0\000" (31)
BLOCKS:
(0-1):375818-375819
TOTAL: 2
Where you can see the creation time:
ctime: 0x5266e438 -- Wed Oct 23 09:46:48 2013
stat -c %w a.txt
%w returns the file creation(birth) date if it is available, which is rare.
Here's the link
As #mikyra explained, creation date time is not stored anywhere.
All the methods above are nice, but if you want to quickly get only last modify date, you can type:
ls -lit /path
with -t option you list all file in /path odered by last modify date.
If you really want to achieve that you can use a file watcher like inotifywait.
You watch a directory and you save information about file creations in separate file outside that directory.
while true; do
change=$(inotifywait -e close_write,moved_to,create .)
change=${change#./ * }
if [ "$change" = ".*" ]; then ./scriptToStoreInfoAboutFile; fi
done
As no creation time is stored, you can build your own system based on inotify.
Cited from https://unix.stackexchange.com/questions/50177/birth-is-empty-on-ext4/131347#131347 , the following shellscript would work to get creation time:
get_crtime() {
for target in "${#}"; do
inode=$(stat -c %i "${target}")
fs=$(df "${target}" | tail -1 | awk '{print $1}')
crtime=$(sudo debugfs -R 'stat <'"${inode}"'>' "${fs}" 2>/dev/null | grep -oP 'crtime.*--\s*\K.*')
printf "%s\t%s\n" "${target}" "${crtime}"
done
}
even better:
lsct ()
{
debugfs -R 'stat <'`ls -i "$1" | (read a b;echo -n $a)`'>' `df "$1" | (read a; read a b; echo "$a")` 2> /dev/null | grep --color=auto crtime | ( read a b c d;
echo $d )
}
lsct /etc
Wed Jul 20 19:25:48 2016
Another trick to add to your arsenal is the following:
$ grep -r "Copyright" /<path-to-source-files>/src
Generally speaking, if one changes a file they should claim credit in the “Copyright”. Examine the results for dates, file names, contributors and contact email.
example grep result:
/<path>/src/someobject.h: * Copyright 2007-2012 <creator's name> <creator's email>(at)<some URL>>

Resources