[SOLVED]Bash commands and scripts in Lazarus.
lazarus / 32-Linux

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johnathan · 2023-10-17 17:55

Hi
Can anybody help

I would like to run bash and/or bash script from within Lazarus if
this is possible.

Things I am already able to do in Lazarus.
Read a text file into a filelistbox and process the information in
Lazarus for example rename a list of files to another directory.

As a starter I would like to run the following bash command from
inside a Lazarus program. I will not be affended if it is very simple
as it needs to be for me.
Obviously  the bash command can be run externally and then load the
file into Lazarus or read the file names from a filelistbox into a
listbox but I would like try to expand my use of Lazarus.

(bash command)    ls -1 >  /mnt/trials/fileslist.txt 

If you can help many thanks

john

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TRon · 2023-10-17 23:19

Quote from: johnathan on October 17, 2023, 07:55:02 pmI would like to
run bash and/or bash script from within Lazarus if this is possible.
Yes, that is possible. See wiki executing external commands.

Quote(bash command)    ls -1 >  /mnt/trials/fileslist.txt 
Especially the piping that you show there is making things overly
complicated for nothing. You can 'catch' the output from an external
command yourself.

I made up some simple example (showing some variations) for Free
Pascal using RunCommand (afaik the most simplified version to run an
external command that also 'catches' the output). It can easily be
integrated into your Lazarus project. The resulting output is by
default stored in a string that you can assign to a memo (property
text) or added to a memo.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i program
run; {$mode objfpc}{$H+} uses  classes, process; procedure dodo;const 
cmd_ls    = '/bin/ls';  cmd_bash  = '/bin/bash';  cmd_chmod =
'chmod';var  rc_result: string;  Line: string;  Lines:
TStringList;begin  // run ls command directly (with full path) 
writeln('>$ ', cmd_ls, ' -l');  if RunCommand(cmd_ls, ['-l'],
rc_result) then  begin    writeln('output:');    writeln(rc_result); 
 writeln;    writeln('alternative way of output:');    Lines :=
TStringList.Create;    Lines.Text := rc_result;    for Line in Lines 
   do Writeln(Line);    Lines.Free;  end  else writeln('error running
command ', cmd_ls);  writeln;   // run s command directly (without
path)  writeln('>$ ', 'ls -l');  if RunCommand('ls', ['-l'],
rc_result) then  begin    writeln('output:');    writeln(rc_result); 
end  else writeln('error running command ', 'ls -l');  writeln;   //
run ls command using bash  writeln('>$ ', cmd_bash, ' -c ls -l');  if
RunCommand(cmd_bash, ['-c', 'ls -l'], rc_result) then  begin   
writeln('output:');    writeln(rc_result);  end  else writeln('error
running command ', cmd_bash);  writeln;   // run bash internal
command  writeln('>$ ', cmd_bash, ' -c compgen -b');  if
RunCommand(cmd_bash, ['-c', 'compgen -b'], rc_result) then  begin   
writeln('output:');    writeln(rc_result);  end  else writeln('error
running command ', cmd_bash);  writeln;   // create a bash script
file  writeln('creating hello.sh script');  Lines :=
TStringList.Create;  Lines.Add('#! ' + cmd_bash);  Lines.Add('echo
"Hello bash"');  Lines.SaveToFile('hello.sh');  Lines.Free; 
writeln;   // run chmod commnand directly (without path) to make the
script executable  writeln('>$ ', cmd_chmod, ' u+x hello.sh');  if
RunCommand(cmd_chmod, ['u+x', 'hello.sh'], rc_result) then  begin   
Writeln('modified bash script file permissions');  end  else
writeln('error running command ', cmd_chmod, ' unable to modify file
permissons');  writeln;   // run the script directly  writeln('>$ ',
'hello.sh');  if RunCommand('hello.sh', [], rc_result) then  begin   
writeln('output:');    writeln(rc_result);  end  else writeln('error
running script');  writeln;end; begin  dodo;end. 
I am not 100% sure if running it from Lazarus requires the full path
to the commands that are being executed (it works when started from a
bash terminal window) but you'll notice that soon enough and can
easily be fixed if that would to be the case.

Seeing that you do not have many posts icw your question, I assume you
are new to Lazarus in which case note that writeln's do not work with
Lazarus unless you start your Lazarus application form a terminal
window. If you want to 'fix' that then replace the writeln's with
adding the strings to a memo or stringlist (or whatever is most
convenient for your application)

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johnathan · 2023-10-23 17:16

Hi
Thanks for the reply. I have not had any success so far but will
continue to experiment.
I notice that runcommand has been depreciated in Linux which could be
a problem.
Meanwhile I have no trouble using bash to generate  ".txt" with bash
to obtain the data I require and using Linux Lazarus IDE to process
the data within them.

Thanks for your time

john

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marcov · 2023-10-23 18:54

Quote from: johnathan on October 23, 2023, 07:16:27 pm
I notice that runcommand has been depreciated in Linux which could be
a problem.

Runcommand is not deprecated, some older forms of the command are
deprecated in favor of newer ones.

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TRon · 2023-10-24 09:01

Quote from: johnathan on October 23, 2023, 07:16:27 pmThanks for the
reply. I have not had any success so far but will continue to
experiment.
You would have to be more specific than that in case you require
additional help. All I can say is that it works for me tm (with
Lazarus as well).

QuoteI notice that runcommand has been depreciated in Linux which
could be a problem.
As stated by marcov, only a specific version of runcommand, see also
manual :

QuoteThe version using CmdLine attempts to split the command line in a
binary and separate command-line arguments. This version of the
function is deprecated.

QuoteMeanwhile I have no trouble using bash to generate  ".txt" with
bash to obtain the data I require and using Linux Lazarus IDE to
process the data within them.
And I emphasize again that runcommand returns the output of the
command into a string (no matter how many lines that output contains
as the line separators are part of that one string as well), so there
would be no need to use bash and/or pipe the output from the executed
command to a textfile to then have to read it in order to do something
with the output.

See also attachment.

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johnathan · 2023-10-30 22:06

Hi

A few more details as suggested.
Please note I am only a desktop computer user having never been
involved in the computer industry.

Reason for program:
I have several hundred (.flac) audio files which have file names in
sequence af10001 af10002 etc.

Aim:
To produce a set of file names to replace the original file with a new
file name, “POSIX compatible”, consisting of the title, and preserving
the original file.
Then to change the title data in the new file combining the title and
artist.

Progress:
While experimenting with theis I have copied just a few of the files
to a separate folder for “safety”
1.   I have extracted the metadata from all files to give  3 text
files (.txt)    with lists of, file names, title, artist. For this I
have written a bash    script using metaflac command.
2.   Loading the 3 text files into Lazarus as stringlists and then
processing them. I have generated the required file names and renamed
and saved them, also generating a text file containing list of the new
titles.

Todo:
Write a bash script using metaflac to delete the original title
metadata in the new file and to replace it with the new title.

I needed to know if I could run a “bash command” and/or “bash script”
within Lazarus rather the having to switch from one to the other. To
do this and not having a great deal of experience I started by asking
something simple
eg.
(bash command) ls -1 > /mnt/trials/fileslist.txt

Thanks
john

----------------------------------------------------------------------
TRon · 2023-10-31 18:35

Quote from: johnathan on October 30, 2023, 11:06:03 pmProgress:
While experimenting with theis I have copied just a few of the files
to a separate folder for “safety”
1.   I have extracted the metadata from all files to give  3 text
files (.txt)    with lists of, file names, title, artist. For this I
have written a bash    script using metaflac command
2.   Loading the 3 text files into Lazarus as stringlists and then
processing them. I have generated the required file names and renamed
and saved them, also generating a text file containing list of the new
titles.
My example was made with the intention to show you that it is not
necessary to use a bash script, nor that it is necessary to store the
output of that script to (separate) files. You can execute the
metaflac terminal command directly using runcomand and 'catch' its
output into a string and/or store that string into a stringlist. That
is what you should be able to get/understand from the posted example
(albeit the example uses other terminal commands to show different
approaches).

QuoteTodo:
Write a bash script using metaflac to delete the original title
metadata in the new file and to replace it with the new title.
Sorry to have to be persistent in my answer but there is no need to
create a bash script. You can if you must and/or want to but really it
is making things complicated for nothing.

QuoteI needed to know if I could run a “bash command” and/or “bash
script” within Lazarus rather the having to switch from one to the
other. To do this and not having a great deal of experience I started
by asking something simple
eg.
(bash command) ls -1 > /mnt/trials/fileslist.txt
And the answer to that particular question is yes you can.

The part what I do not understand is that you wrote that you do rather
not want to switch between one or another. I read that as: you do not
want to switch between running a bash command and/or running a bash
script. If you leave out bash from the equation then the only thing
left is to run the terminal commands directly and you can do that as
showed per my example.

My example is/was meant to show that you can use any of the 3
approaches:
- run a terminal command directly (not using bash or scripts)
- run a command using/through bash
- run a shell/terminal script

So you can choose whatever approach is more convenient for you.

Or to put it into other words: I still have no clue what it is that
you actually have a problem with.

Am I perhaps confusing you by the fact that I stated that this is a
Free Pascal example that requires to be started using a terminal ?

Because that is only required for the writeln's so that the example is
able to provide some feedback on what is happening. For such simple
examples I use Free Pascal and not Lazarus (that is why I posted a
picture of a Lazarus example using the same code but then uit outputs
the result(s) to a TMemo control instead). So that picture is from a
pure desktop only application (with the exception that it relies on
the OS to provide us access to the terminal (commands)).

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johnathan · 2023-11-01 11:51

Hi again.
Thanks for all your input and your patience for those of us who have a
limited ability and knowledge.

I will mark the topic as SOLVED as the initial question has been
answered ie can bash be used in Lazarus IDE.

The term “switch” was used to indicate that I would like to remain
within the Lazarus IDE but would use either “bash or bash script”.

I have printed off your replies and will continue to try and
understand how it works.

Thanks again for your input

Regards john

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TRon · 2023-11-03 20:48

Quote from: johnathan on November 01, 2023, 12:51:46 pmThe term
“switch” was used to indicate that I would like to remain within the
Lazarus IDE but would use either “bash or bash script”.
The example shows that both are possible.

QuoteI have printed off your replies and will continue to try and
understand how it works.
If you have a specific question then please elaborate.

I am not familiar with metaflac (though I tried as soon as you
mentioned the command for the first time) but you can execute it
directly from within Lazarus (just like the example: "run ls command
directly" either with full path or without, just replacing ls with
metaflac, using bash or otherwise)

The metaflac command itself is a bit peculiar with accepting some
parameters because of the quoting style it seem to require for some
arguments f.e. --set-tag=field where field is declared as "NAME=VALUE"
(note the quotes, they seem to be mandatory and can cause issues with
runcommand when those quotes are not applied correctly which for
example seems to be --set-tag="artist=some artist name" and not --set-
tag=artist="some artist name" or "--set-tag=artist=some artist name").

QuoteThanks again for your input
You're welcome though I have a feeling that you are still struggling
with either the code or the concept.

Please don't hesitate to ask but do not expect others to write code
for you especially when not providing any example code (if even a
metaflac example commandline or bash script that could be converted to
Pascal using only runcommand (using bash or otherwise).

Do note that I expressed why using your ls piped ls example code
(which can literally be executed with runcommand using bash or sh) is
a bad idea and I therefor deem it as a not so good example to show
what you are intending to accomplish when looking at the whole
picture.

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johnathan · 2023-11-30 12:17

Hi Again
As you have said  I am  still struggling with either the code or the
concept.

I have now completed my aim to process hundreds of ".flac" files and
all my programs/scripts work perfectly as required.
I have not given up hope of making this a single program and will
spend continue to try and master it.

My bash script "bashmusic.sh generates all the required data in ".txt"
files to load into the Lazarus executable.

My Lazarus executable  "musictitles5"  then processes the data to be
used for changing the metadata in the files and renaming them  files
with  "POSIX"  compatible filenames.

My bash script "trial07.sh" then changes the metadata moves the
processed files to the required directories and cleans the used
temporary directories and temporary .txt files.

Thanks  for the all the input

John

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TRon · 2023-11-30 17:23

Quote from: johnathan on November 30, 2023, 01:17:57 pmAs you have
said  I am  still struggling with either the code or the concept.
Like said, if you have hands on practical (bash) code that you want
converted then show us. Without it, it is nearly impossible to come up
with an example that matches your needs/requirements simply because we
do not know what those needs/requirements are.

All I can say for now is that everything bash can do, Pascal and/or
Lazarus can do ranging from executing commands to processing
directories/files recursively matching a certain mask, retrieving the
output from commands and processing that output to feed to another
command etc.

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johnathan · 2023-12-02 15:46

Hi

For now I will be busy running my program and scripts to process some
of the hundreds of  .flac files i have.

Hopefully in the new year I will try again to work out what I need to
do.

Attached is the bash script that I use to produce the input for my
Lazarus program.
It may not be good programming, as I have only been writing scripts
for a few months, but it does exactly what I need.

I tried to attach as a libreoffice .odt file before I found that that
format was not allowed.

Regards john

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TRon · 2023-12-03 01:52

Quote from: johnathan on December 02, 2023, 04:46:02 pmAttached is the
bash script that I use to produce the input for my Lazarus program.
Something to work with...

QuoteIt may not be good programming, as I have only been writing
scripts for a few months, but it does exactly what I need.
That doesn't really matter. If you wish to do it purely in Lazarus
then it requires a different angle/mindset to solve/approach the
issue.

Code: Bash  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i
oldnumber=""while IFS= read -r line ; do oldnumber=("$line")done <
"$data2/music29.txt" echo "old batch number " $oldnumberechoecho enter
batchread batchrunnumber=$batch I have no idea what this first part of
your bash script does or is suppose to be doing so I needed to skip
that part,

The rest of your bash script can be converted to pascal with:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i program
bashbash; {$mode objfpc}{$H+}{.$define mysetup} // for my personal
setup not matching yours. //
https://forum.lazarus.freepascal.org/index.php/topic,64932.0.html//
https://wiki.freepascal.org/FindAllFiles uses  classes, process,
fileutil, sysutils; const  {$ifdef mysetup}  source = './flacs'; 
{$else}  source = '/mnt/music/bashmusic/source1';  {$endif} 
FindRecursive = false;  // search source directory recursively for
flac files (true (=yes)/false (=no)). Your batch file
doesn't.  procedure Print(s: string); overload;begin  {$ifdef
mysetup}  writeln(s);  {$else}  // in case you wish to use lazarus and
display the output to a memo  // then your code should be looking
something like:  Form1.InfoMemo.Append(s);  {$endif}end; procedure
Print(s: string; const args: array of const); overload;begin 
print(Format(s, args));end;  procedure test;var  FileNames:
TStringList;  Filename : string;   command  : string;  parameter:
string;  rc_result: string;   Artist: string;  Title : string;  Album
: string;begin  // create a stringlist that will contain the found
filenames  FileNames := TStringList.Create;  try    // find all the
files in directory source that matches the mask *.flac   
FindAllFiles(Filenames, source, '*.flac', FindRecursive);   
print('found %d files.', [FileNames.Count]);     // iterate through
the FileNames list    // equivalent to your bash line: for filename in
$source/*.flac ; do    for FileName in FileNames do    begin     
print('');      print('handling filename %s', [Filename]);       //
equivalent of your bash line: metaflac --show-tag=artist $filename   
 command   := 'metaflac';      parameter := '--show-tag=artist';     
if RunCommand(command, [parameter, FileName], rc_result) then     
begin        Artist := rc_result.TrimRight;      end      else
print('error running command %s %s', [command, parameter]);       //
equivalent of your bash line: metaflac --show-tag=title $filename    
command   := 'metaflac';      parameter := '--show-tag=title';      if
RunCommand(command, [parameter, FileName], rc_result) then      begin 
      Title := rc_result.TrimRight;      end      else print('error
running command %s %s', [command, parameter]);       // equivalent of
your bash line: metaflac --show-tag=album $filename      command   :=
'metaflac';      parameter := '--show-tag=album';      if
RunCommand(command, [parameter, FileName], rc_result) then      begin 
      Album := rc_result.TrimRight;      end      else print('error
running command %s %s', [command, parameter]);       // show the
resulting answers:      print('Filename = %s', [Filename]);     
print('Artist   = %s', [Artist]);      print('Title    = %s',
[Title]);      print('Album    = %s', [Album]);    end;   finally;   
FileNames.Free;  end;end; begin  test;end. 
I wrote it as a pure Free Pascal command line example but it should be
easy enough to copy-paste the interesting parts to your Lazarus
project in order to test. Make sure to backup your original project
first before tinkering with code from someone else (things might
explode  ).

And the output with a test album:
Code: [Select]found 9 files.

handling filename flacs/9 - 52nd Street.flac
Filename = flacs/9 - 52nd Street.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=52nd Street
Album    = ALBUM=52ND STREET

handling filename flacs/8 - Until The Night.flac
Filename = flacs/8 - Until The Night.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Until The Night
Album    = ALBUM=52ND STREET

handling filename flacs/7 - Half A Mile Away.flac
Filename = flacs/7 - Half A Mile Away.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Half A Mile Away
Album    = ALBUM=52ND STREET

handling filename flacs/6 - Rosalinda's Eyes.flac
Filename = flacs/6 - Rosalinda's Eyes.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Rosalinda's Eyes
Album    = ALBUM=52ND STREET

handling filename flacs/5 - Stiletto.flac
Filename = flacs/5 - Stiletto.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Stiletto
Album    = ALBUM=52ND STREET

handling filename flacs/4 - Zanzibar.flac
Filename = flacs/4 - Zanzibar.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Zanzibar
Album    = ALBUM=52ND STREET

handling filename flacs/3 - My Life.flac
Filename = flacs/3 - My Life.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=My Life
Album    = ALBUM=52ND STREET

handling filename flacs/2 - Honesty.flac
Filename = flacs/2 - Honesty.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Honesty
Album    = ALBUM=52ND STREET

handling filename flacs/1 - Big Shot.flac
Filename = flacs/1 - Big Shot.flac
Artist   = ARTIST=BILLY JOEL
Title    = TITLE=Big Shot
Album    = ALBUM=52ND STREET

Simply lovely that upcase tagging style  :'(

It might perhaps not be the exact output you are expecting but strings
are pretty easy to manipulate and it is fairly easy to extract the
bits and pieces that you might be interested in. I can't change what
the metaflace tool actually returns (such as the CRLF at the end of
the return value when requesting a tag so the code removes it with
TrimRight).

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johnathan · 2023-12-05 10:58

Hi
Thanks again for all your input.
The first part is just to keep a log of the batches that I process and
I could quite easily put this into my Lazarus program.

I tend to convert any data I read into Lazarus to lowercase which
keeps things simple for me.

I will as you say backup my original Lazarus project, I tend to do
this by saving everything with a new  lpi and pas filenames in a new
directory.

I will in due course attempt to use some of your code so that I can
use Lazarus only, and will let you know how it goes although it may be
in the new year.

Regards  john

21st. December 2023

Christmas has come early, thanks to your suggestions.
Could not wait for the new year so have started writing  a Lazarus
version of some parts of your code into my project.
About half way though adding the (bashmusic2.sh) to my program and so
far no problems and works as as required.
It looks like I will be able to run the whole thing from Lazarus now.
I have also added Lazarus code to copy files automatically to the
source and destination directories.

My grateful thanks, hope  the new year brings good health to all.

john