I need something similar:
$ tclsh --run-command puts hello
to print out: hello.
Like -c in bash.
The simplest is to create a TCL script: runner.tcl with the following content:
#runner.tcl
eval $argv
Use:
$ tclsh runner.tcl puts hello
Related
Use the command flag looked like a solution but it doesn't work
Inside the following shell:
nix shell github:nixos/nixpkgs/nixpkgs-unstable#hello
the path contain a directory with an executable hello
I've tried this:
nix shell github:nixos/nixpkgs/nixpkgs-unstable#hello --command echo $PATH
I can't see the hello executable
My eyes are not the problem.
diff <( echo $PATH ) <( nix shell github:nixos/nixpkgs/nixpkgs-unstable#hello --command echo $PATH)
It see no difference. It means that the printed path doesn't not contains hello.
Why?
The printed path does not contain hello because if your starting PATH was /nix/var/nix/profiles/default/bin:/run/current-system/sw/bin, then you just ran:
nix shell 'github:nixos/nixpkgs/nixpkgs-unstable#hello' --command \
echo /nix/var/nix/profiles/default/bin:/run/current-system/sw/bin
That is to say, you passed your original path as an argument to the nix shell command, instead of passing it a reference to a variable for it to expand later.
The easiest way to accomplish what you're looking for is:
nix shell 'github:nixos/nixpkgs/nixpkgs-unstable#hello' --command \
sh -c 'echo "$PATH"'
The single quotes prevent your shell from expanding $PATH before a copy of sh invoked by nix is started.
Of course, if you really don't want to start any kind of child shell, then you can run a non-shell tool to print environment variables:
nix shell 'github:nixos/nixpkgs/nixpkgs-unstable#hello' --command \
env | grep '^PATH='
I am using python doit module as a GNU make replacement.
Seems that doit is running actions on /bin/sh:
pedro#Gen83-ubuntu:~$ echo $SHELL
/bin/bash
pedro#Gen83-ubuntu:~$ doit merge_phased
. phase_dataset:15
/bin/sh: 1: [[: not found
TaskError - taskid:phase_dataset:15
Command error: '[[ ! -d phasing ]] && mkdir phasing' returned 127
########################################
phase_dataset:15 <stdout>:
I would like to use /bin/bash. I could not find how to accomplish that in the documentation.
if its a sh file then you can add this at the top to run with bash
#!/bin/bash
or
#!/bin/ksh
to run with ksh
0
I am trying to run this command and getting an error:
docker exec 19eca917c3e2 cat "Hi there" > /usr/share/ngnix/html/system.txt
/usr/share/ngnix/html/system.txt: No such file or directory
A very simple command to create a file and write in it, I tried echo and that one too didn't work.
The cat command only works on files, so cat "Hi there" is incorrect.
Try echo "Hi there" to output this to standard out.
You are then piping the output to /usr/share/ngnix/html/system.txt. Make sure the directory /usr/share/ngnix/html/ exists. If not create it using
mkdir -p /usr/share/ngnix/html
I presume you are trying to create the file in the container.
You have several problems going on, one of which #Yatharth Ranjan has addressed - you want echo not cat for that use.
The other is, your call is being parsed by the local shell, which is breaking it up into docker ... "hello world" and a > ... system.txt on your host system.
To get the pipe into file to be executed in the container, you need to explicity invoke bash in the container, and then pass it the command:
docker exec 12345 /bin/sh -c "echo \"hello world\" > /usr/somefile.txt"
So, here you would call /bin/sh in the container, pass it -c to tell it a shell command follows, and then the command to parse and execute is your echo "hello world" > the_file.txt.
Of course, a far easier way to copy files into a container is to have them on your host system and then copy them in using docker cp: (where 0123abc is your container name or id)
docker cp ./some-file.txt 01234abc:/path/to/file/in/container.txt
I would like to compare 2 file and show the difference between files
when I use the following :
exec sh -c "diff -w file1 file2 \|grep \<"
but no result is shown and the script is brokeen
what's wrong with the tcl command ?
The following will work:
puts [exec sh -c "diff -w file1 file2 |grep \\<"]
The < needs to be double-backslashed, and the output should be printed.
I'm trying to do this:
run "echo -n 'foo' > bar.txt"
and the contents of bar.txt ends up being:
-n foo \n
(With \n representing an actual newline)
I use run for other commands like rm -rf and, to my knowledge, it works fine.
I just found this in man echo:
Some shells may provide a builtin echo command which is similar or identical to this utility. Most notably, the builtin echo in sh(1) does not accept the -n option. Consult the builtin(1) manual page.
My version of bash has an echo builtin but seems to be respecting the -n flag. It looks like the shell on your deployment machine doesn't, in which case using the full path to the echo binary might do what you want here:
run "/bin/echo -n 'foo' > bar.txt"
It appears as though the -n flag isn't being interpreted as a flag by the shell. If, from the command line, one executes echo -Y hi, the output will be -Y hi.