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Full Discussion: Issue with writing a pipe
Top Forums Shell Programming and Scripting Issue with writing a pipe Post 303045208 by sea on Friday 13th of March 2020 01:53:48 PM
Old 03-13-2020
Ok did some more research.

While this confirms my confusion (missing better words here..), I learned some new things allthough most of it was known.
Asdide the fact that 'echo' is both, for some reason I always thought that /bin/echo was the echo used when calling echo, and thus not realized the builtin existed - or that they are different 'code'.
How to distinguish between builtin and external util? (e.g. echo) - Unix & Linux Stack Exchange


This one here seems to confirm my most recent assumptions as since today:
shell - Which are the standard commands available in every Linux based distribution? - Unix & Linux Stack Exchange

That I most likley could rely on the bash builtin 'echo' for the use of SWARM.
But none of that sounded certain, so I then I followed a link of the 2nd post (46 up votes) about the standarized commands by PSIX and ended up here: echo

Now, when you go down to the 'Application Usage' section, you'll see this part:
Code:
It is not possible to use echo portably across all POSIX systems unless both -n (as the first argument) and escape sequences are omitted.

The printf utility can be used portably to emulate any of the traditional behaviors of the echo utility as follows (assuming that IFS has its standard value or is unset):

The historic System V echo and the requirements on XSI implementations in this volume of POSIX.1-2017 are equivalent to:

printf "%b\n" "$*"

The BSD echo is equivalent to:

if [ "X$1" = "X-n" ]
then
    shift
    printf "%s" "$*"
else
    printf "%s\n" "$*"
fi

New applications are encouraged to use printf instead of echo.

Now my final question, which of these 2 examples would you recomend?
I have to ask this, because I lack the practical experience of actual daily usage on different systems.

Anyway, I'm going to try this out now.
Lets see which works better as expected.

At least I know now that it wasnt a waste of time preparing $ECHO to use printf, what a relieve! Smilie
 

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BUILTIN(1)						    BSD General Commands Manual 						BUILTIN(1)

NAME
builtin, !, %, ., :, @, [, {, }, alias, alloc, bg, bind, bindkey, break, breaksw, builtins, case, cd, chdir, command, complete, continue, default, dirs, do, done, echo, echotc, elif, else, end, endif, endsw, esac, eval, exec, exit, export, false, fc, fg, filetest, fi, for, foreach, getopts, glob, goto, hash, hashstat, history, hup, if, jobid, jobs, kill, limit, local, log, login, logout, ls-F, nice, nohup, notify, onintr, popd, printenv, printf, pushd, pwd, read, readonly, rehash, repeat, return, sched, set, setenv, settc, setty, setvar, shift, source, stop, suspend, switch, telltc, test, then, time, times, trap, true, type, ulimit, umask, unalias, uncomplete, unhash, unlimit, unset, unsetenv, until, wait, where, which, while -- shell built-in commands SYNOPSIS
See the built-in command description in the appropriate shell manual page. DESCRIPTION
Shell builtin commands are commands that can be executed within the running shell's process. Note that, in the case of csh(1) builtin com- mands, the command is executed in a subshell if it occurs as any component of a pipeline except the last. If a command specified to the shell contains a slash '/', the shell will not execute a builtin command, even if the last component of the specified command matches the name of a builtin command. Thus, while specifying ``echo'' causes a builtin command to be executed under shells that support the echo builtin command, specifying ``/bin/echo'' or ``./echo'' does not. While some builtin commands may exist in more than one shell, their operation may be different under each shell which supports them. Below is a table which lists shell builtin commands, the standard shells that support them and whether they exist as standalone utilities. Only builtin commands for the csh(1) and sh(1) shells are listed here. Consult a shell's manual page for details on the operation its builtin commands. Beware that the sh(1) manual page, at least, calls some of these commands ``built-in commands'' and some of them ``reserved words''. Users of other shells may need to consult an info(1) page or other sources of documentation. Commands marked ``No**'' under External do exist externally, but are implemented as scripts using a builtin command of the same name. Command External csh(1) sh(1) ! No No Yes % No Yes No . No No Yes : No Yes Yes @ No Yes No [ Yes No Yes { No No Yes } No No Yes alias No** Yes Yes alloc No Yes No bg No** Yes Yes bind No No Yes bindkey No Yes No break No Yes Yes breaksw No Yes No builtin No No Yes builtins No Yes No case No Yes Yes cd No** Yes Yes chdir No Yes Yes command No** No Yes complete No Yes No continue No Yes Yes default No Yes No dirs No Yes No do No No Yes done No No Yes echo Yes Yes Yes echotc No Yes No elif No No Yes else No Yes Yes end No Yes No endif No Yes No endsw No Yes No esac No No Yes eval No Yes Yes exec No Yes Yes exit No Yes Yes export No No Yes false Yes No Yes fc No** No Yes fg No** Yes Yes filetest No Yes No fi No No Yes for No No Yes foreach No Yes No getopts No** No Yes glob No Yes No goto No Yes No hash No** No Yes hashstat No Yes No history No Yes No hup No Yes No if No Yes Yes jobid No No Yes jobs No** Yes Yes kill Yes Yes Yes limit No Yes No local No No Yes log No Yes No login Yes Yes No logout No Yes No ls-F No Yes No nice Yes Yes No nohup Yes Yes No notify No Yes No onintr No Yes No popd No Yes No printenv Yes Yes No printf Yes No Yes pushd No Yes No pwd Yes No Yes read No** No Yes readonly No No Yes rehash No Yes No repeat No Yes No return No No Yes sched No Yes No set No Yes Yes setenv No Yes No settc No Yes No setty No Yes No setvar No No Yes shift No Yes Yes source No Yes No stop No Yes No suspend No Yes No switch No Yes No telltc No Yes No test Yes No Yes then No No Yes time Yes Yes No times No No Yes trap No No Yes true Yes No Yes type No** No Yes ulimit No** No Yes umask No** Yes Yes unalias No** Yes Yes uncomplete No Yes No unhash No Yes No unlimit No Yes No unset No Yes Yes unsetenv No Yes No until No No Yes wait No** Yes Yes where No Yes No which Yes Yes No while No Yes Yes SEE ALSO
csh(1), echo(1), false(1), info(1), kill(1), login(1), nice(1), nohup(1), printenv(1), printf(1), pwd(1), sh(1), test(1), time(1), true(1), which(1) HISTORY
The builtin manual page first appeared in FreeBSD 3.4. AUTHORS
This manual page was written by Sheldon Hearn <sheldonh@FreeBSD.org>. BSD
December 21, 2010 BSD
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