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bash printf vs echo

You can pass the -n option to suppress the printing of the newline. Depending on the unix variant, the shell and the shell options, it may also interpret some escape sequences beginning with \, and it may treat the first argument(s) as options if they start with -. No newline is added unless you specify one. There's a core of features that is specified by POSIX, but then there are a lot of extensions. Sven Mascheck has a nice page that shows the extent of the problem. Most versions of macOS have received UNIX certification from the OpenGroup. Interpreting a variable as its value is one way of expanding it, but there are a few more you can leverage. echo is useful when it comes to printing the value of a variable or a (simple) line, but that's all there is to it. In the below-mentioned case, when ${array[0]} is enclosed within single quotes, it gets evaluated and 10 is printed, as it is the 0th element of the array but when enclosed within single quotes, the literal identity of $ is retained and it does not get evaluated. Inside ksh93, the getconf builtin (enabled with builtin getconf or by invoking command /opt/ast/bin/getconf) is the interface to astgetconf(). Echo is a statement in which it does not return the valueprint. According to the Linux documentation, the following is the syntax for echo command. Probably, if you add the newline character that echo uses by default (except when using -n option) you'll get the same effect. It means their purpose is same , to display something to standard output. And as soon as it sees \c in an argument, it stops outputting (so the trailing newline is not output either). (NB: the last \n is necessary, echo implies it, unless you give the -n option). It knows to interpret them and won't require an -e to do so. It is a good command to display a simple output when you know that the variable's contents will not cause problems. That /bin/echo is the one from FreeBSD which suppresses newline output if the first argument is -n or (since 1995) if the last argument ends in \c, but doesn't support any other backslash sequences required by UNIX, not even \\. Nowadays, echo (1) is only portable if you omit flags and escape sequences. Generating Output With echo command. Because different shells work differently, echo "$string" does not always print the specified string plus a newline. This video also discuss about their differences. Is this a difference in bash versions, or do these uses differ somehow? echo vs printf January 12, 2019 January 12, 2019 jack4it In bash, or generally the family of shell languages, echo and printf are often used to output messages to the screen (or terminal, or tty, or stdout, to earn a few more geek points…). Commands 7, 8, and 9 will not be traced. Syntax : echo [option] [string] The _AST_FEATURES is not meant to be manipulated directly, it is used to propagate AST configuration settings across command execution. Benchmarks First, some background. Will output the content of $var followed by a newline character regardless of what character it may contain. posix mode can be enabled if bash is called as sh or if POSIXLY_CORRECT is in the environment or with the the posix option: xpg_echo expands sequences as UNIX requires: This time, bash is both POSIX and UNIX conformant. Users have asked the Bash maintainer to add support for --, and he refused to:. If you want a newline after the string, write printf '%s\n' "$string". echo always exits with a 0 status, and simply prints arguments followed by an end of line character on the standard output, while printf allows for definition of a formatting string and … Does printf send an extra EOF at the end of its output? If you want to add a link outside your editor, you’ll need to code it into a custom function or add it directly in a theme file. Internal Commands and Builtins. The behavior varies for printf '%10s\n' "$var" in multi-byte locales, there are at least three different outcomes for printf %b '\123'. But in the end, if you stick to the POSIX feature set of printf and don't try doing anything too fancy with it, you're out of trouble. Bash Performance Test - Regex vs If/Else. Any code that would use `echo --' is, by definition, new code and new code should use printf. Theoretically, echo is more efficient because it does not return any value. Chapter 15. Each function needs to be called by a main routine in order to run, thus, it is isolated with other parts of your code and this creates an easy way of code testing. echo is faster on my side (bash 4.3.46). At the end of the day it's a matter of taste and requirements what you use: echo or printf. PDF - Download PHP for free GitHub Gist: instantly share code, notes, and snippets. Otherwise, you could create a new widget area and add the … A function, also known as a subroutine in programming languages is a set of instructions that performs a specific task for a main routine . David Korn realized the mistake and introduced a new form of shell quotes: $'...' which was later copied by bash and zsh but it was far too late by that time. echo is not portable when printing variable values, as it accepts options in them. 2021 Stack Exchange, Inc. user contributions under cc by-sa, https://unix.stackexchange.com/questions/65803/why-is-printf-better-than-echo/65819#65819, A lot of early unix development happened in isolation, and good software engineering principles like, As a note, the one (and maybe only) advantage of having. Display a line of text containing a double quote. Their sh builtin echo is compliant as it's bash (a very old version) built with xpg_echo enabled by default, but their stand-alone echo utility is not. You might want to use printf for its formatting options. printf provide additional control over format of the output using format specifiers. No new line had been printed out as it it in case of when using default setting of echo command. Thanked 4,560 Times in 3,818 Posts. And it defined "printf" as a new, more powerful tool. Could you expand on that? Answered July 13, 2018. printf is like echo on steroids. In ksh93, whether echo expands escape sequences or not and recognises options depends on the content of the $PATH and/or $_AST_FEATURES environment variables. This is a built in command that is mostly used in shell scripts and batch files to output status text to the screen or a file. If $PATH contains a component that contains /5bin or /xpg before the /bin or /usr/bin component then it behave the SysV/UNIX way (expands sequences, doesn't accept options). file=$(echo "$var" | tr ' ' _) is not OK in most implementations (exceptions being yash with ECHO_STYLE=raw (with the caveat that yash's variables can't hold arbitrary sequences of bytes so not arbitrary file names) and zsh's echo -E - "$var"6). env echo -n outputs nothing instead of -n, env echo '\n' outputs \n instead of . printf was introduced with the Ninth Edition System (reference in SUSv3). So what that means is that you can't use echo to display uncontrolled data. POSIX says: if the first argument is -n or any argument contains backslashes, then the behaviour is unspecified. The >&2 part has nothing to do with either echo nor printf.The >& is a shell redirection operator, where in this case it duplicates stdout (implied, though could be referenced explicitly with 1>&2) of the command to stderr ( file descriptor 2). Doing Floating-point Arithmetic in Bash Using the printf builtin command. That means that echo ${month[3]}, after the expansion, translates to echo "Apr". (But even if command 5 is an echo, command 6 still will be traced.) I have heard that printf is better than echo. printf "k\\nk" printf 'k\\nk' 3. Echo vs Print. The UNIX specification is stricter, it prohibits -n and requires expansion of some escape sequences including the \c one to stop outputting. On those echo implementations that support options, there's generally no support of a -- to mark the end of options (the echo builtin of some non-Bourne-like shells do, and zsh supports - for that though), so for instance, it's difficult to output "-n" with echo in many shells. Actually, that's not true, the /bin/bash that Oracle ships with Solaris 11 (in an optional package) seems to be built with --enable-xpg-echo-default (that was not the case in Solaris 10). So while Posix encourages the use of "printf", "echo" is now standard too. One downside of printf is performance because the built-in shell echo is much faster. A more reliable echo can be implemented using printf, like: The subshell (which implies spawning an extra process in most shell implementations) can be avoided using local IFS with many shells, or by writing it like: With bash, at run time, there are two things that control the behaviour of echo (beside enable -n echo or redefining echo as a function or alias): sent the data. The formatting strings are described in the manual page for sprintf. Additionally, functions can be called anytime and repeatedly, this allows you reuse, optimize and minimi… $ echo "text with spaces" | bash -c 'printf "%q" "$(cat)"'; echo text\ with\ spaces For me, this escapes spaces with backslashes; the example in the article escapes them by quoting the whole string. The printf utility has been almost universally available for more than 2 decades and is a built-in in almost all current shells. Echo and print are perhaps one of the most interchanged PHP output. In your case, assuming that blah doesn't start with a - or contain % or \, the only difference between the two commands is that echo adds a newline and printf doesn't. 10.3.2 echo. Now, someone thought it would be nice if we could do things like echo "\n\t" to output newline or tab characters, or have an option not to output the trailing newline character. It offers no formatting option. the xpg_echo bash option and whether bash is in posix mode. It's not a slam dunk to always use printf. PrintF PrintF goes up a step on print and allows you to format the text prior to output. echo prints its argument followed by a newline. In the first argument, all characters except two are interpreted literally: % starts a printf specifier, and \ starts an escape sequence (e.g. After doing that, you'll notice the $_AST_FEATURES environment variable contains UNIVERSE = att. Speed of echo vs print in PHP . To print a double quote, enclose it within single … The POSIX specification actually does tell us to use printf instead in that case. Will output it without the trailing newline character. Other shells/Unix vendors/versions chose to do it differently: they added a -e option to expand escape sequences, and a -n option to not output the trailing newline. The echo utility has been universally available for more than 4 … Both echo and printf are built-in commands (printf is Bash built-in since v2.0.2, 1998). Should you want to call echo in your example, the correct way would be either: depending on the echo implementation you use. Its roots are in the C programming language, which uses a functionby the same name. https://unix.stackexchange.com/questions/65803/why-is-printf-better-than-echo/65807#65807, https://unix.stackexchange.com/questions/65803/why-is-printf-better-than-echo/65808#65808. The difference is that echo sends a newline at the end of its output. printf, on the other hand is more reliable, at least when it's limited to the basic usage of echo. These two commands which are mainly used to place output information to the visitor’s screen, such as like in the web page give the same action. To print a new line we need to supply printf with format string with escape sequence \n ( new line ): $ printf "%s\n" "hello printf" hello printf The format string is applied to each argument: $ printf "%s\n" "hello printf" "in" "bash script" hello printf in bash script Format specifiers That's typically what recent versions of OS/X do to build their /bin/sh. echo Command Examples The two functions vprintf and vsprintf operate as printf and sprintf, but accept a format string and an array of values, instead of individual variables. I'm amazed at how much you know about echo and printf! Why the scare quotes? If you didn't know bash had its own version of printf, then you didn't heed the note in the man page for the printf(1) command: "print", on the other hand, is a non-standard feature of ksh. Now when a standard UNIX echo receives an argument which contains the two characters \ and t, instead of outputting them, it outputs a tab character. For most uses, printf is preferable. They can appear in any order in a command in bourne-like shells. No Unix/Linux implementation/distribution in their right mind would typically do that for /bin/bash though. Recommended for you It is a handy way to produce precisely-formatted output from numerical or textual arguments. printf '%s' "$var". One "advantage", if you want to call it that, would be that you don't have to tell it like echo to interpret certain escape sequences such as \n. Send Text to Standard Output. I had to use prinf to be able to print the literal string "-e". It was added to more widely distributed Unix flavours with 4.3BSD-Reno and with SVR4. For the Love of Physics - Walter Lewin - May 16, 2011 - Duration: 1:01:26. Repeated the results with GNU bash 4.4.12(1), and I've got different results: https://unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/58311#58311, Good reference, but not really an answer to the question, nor an explanation why, https://unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/58358#58358, https://unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/58315#58315, https://unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/242211#242211, Difference between printf and echo in bash [duplicate]. Those specifications don't really come to the rescue here given that many implementations are not compliant. :-/, Same thing, echo is faster (GNU bash, version 4.3.33(1)-release). But apparently, there are other differences, and I would like to inquire what they are as well as if there are specific cases when to use one vs the other. (shebang) command 1 command 2 command 3 set -x command 4 command 5 command 6 set +x command 7 command 8 command 9 and Commands 4, 5, and 6 will be traced — unless one of them is an echo, in which case it will be executed but not traced. In other words, if you're writing a script and it is taking external input (from the user as arguments, or file names from the file system...), you can't use echo to display it. I can recall only one instance from my experience where I had to use printf because echo didn't work for feeding some text into some program on RHEL 5.8 but printf did. With multiple arguments, they are separated by spaces. printf has more control over the output format. Using one over the other is not likely to yield any performance improvement in your application. Use echo command to display a line of text or a variable value. Now, there also are differences between printf implementations. Note that in POSIX mode, bash is still not POSIX conformant as it doesn't output -e in: The default values for xpg_echo and posix can be defined at compilation time with the --enable-xpg-echo-default and --enable-strict-posix-default options to the configure script. I faced such a problem recently while writing a script. To output any string or number or text on the terminal, type the following command and press enter. Note the last \n in printf. If it finds /ucb or /bsd first or if $_AST_FEATURES7 contains UNIVERSE = ucb, then it behaves the BSD3 way (-e to enable expansion, recognises -n). For instance, you'd do builtin getconf; getconf UNIVERSE = att to change the UNIVERSE setting to att (causing echo to behave the SysV way among other things). Will output it without the trailing newline character. echo always exits with a 0 status, and simply prints arguments followed by an end of line character on the standard output, while printf allows for definition of a formatting string and gives a non-zero exit status code upon failure. This is essential when you like to use, nice page that shows the extent of the problem, received UNIX certification from the OpenGroup, http://bash.cyberciti.biz/guide/Echo_Command. Some have a -E to disable escape sequences, some have -n but not -e, the list of escape sequences supported by one echo implementation is not necessarily the same as supported by another. As soon as you need something more complex, you shoud use printf which is portable (i.e. These gave me the contrary results. behave the same regardless of the OS) and allows much better formatting, being designed from the same name C function. Strictly speaking, you could also count that FreeBSD/macOS /bin/echo above (not their shell's echo builtin) where zsh's echo -E - "$var" or yash's ECHO_STYLE=raw echo "$var" (printf '%s\n' "$var") could be written: And zsh's echo -nE - "$var" (printf %s "$var") could be written. If you want to literally print the string "-e", you will have difficulties doing it with echo. Even some certified systems like macOS5 are not compliant. printf prints a formatted string to the standard output. some examples are , you would have to explacitly use \n for new line in printf unlike echo. But is there really a difference between them? echo [option(s)][string(s)] Now, we shall see the different ways in which we can output the text on the terminal. But testing them with time (also built-in) the results say otherwise: Telling printf to add newline characters, just as echo does by default: that is obviously slower than without printing the \n, but yet faster than echo. Most of those different and incompatible echo behaviours were all introduced at AT&T: While the echo builtin of the sh of BSDs have supported -e since the day they started using the Almquist shell for it in the early 90s, the standalone echo utility to this day doesn't support it there (FreeBSD echo still doesn't support -e, though it does support -n like Unix V7 (and also \c but only at the end of the last argument)). Initially, echo didn't accept any option and didn't expand anything. Why wouldn't it be an advantage? printf can basically do what the C version of it can do. printf interprets its first argument as a format, and subsequent arguments as arguments to the % specifiers. By default echo will display the string and print a newline character after it. Both echo and printf are built-in commands (printf is Bash built-in since v2.0.2, 1998). Here is probably the best description of echo vs printf, http://www.in-ulm.de/~mascheck/various/echo+printf/. For trivial messages (no escape sequences, no options), echo is fine. The phrase "if you want to call it that" implies pretty strongly that you think it isn't. On some shells like bash¹ or ksh93² or yash ($ECHO_STYLE variable), the behaviour even depends on how the shell was compiled or the environment (GNU echo's behaviour will also change if $POSIXLY_CORRECT is in the environment and with the version4, zsh's with its bsd_echo option, some pdksh-based with their posix option or whether they're called as sh or not). Your wording implies that it isn't necessarily a real advantage. (Some shells provide extensions that supply additional conversion specifiers.) And, item 3 within the array points to "Apr" (remember: the first index in an array in Bash is [0]). did not send the "blah" command to the server listening on 8125, whereas. There is a large set of conversion specifiers that behave the same way on all systems and in all shells. The echo(1) command displays the specified text on the screen.You specify the string to display after the echo command. It's a trade off between portability and performance. What is the difference between the printf function in bash and the echo function? echo command in linux is used to display line of text/string that are passed as an argument . Previous Thread | Next Thread Use printf (1) instead, if you need more than plain text. It's not; echo has never behaved this way. They will make you ♥ Physics. Since coreutils 8.31 (and this commit), GNU echo now expands escape sequences by default when POSIXLY_CORRECT is in the environment, to match the behaviour of bash -o posix -O xpg_echo's echo builtin (see bug report). \n for a newline character). The proper way would be to monitor, https://unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/58312#58312. echo "Hello World" All in all, you don't know what echo "$var" will output unless you can make sure that $var doesn't contain backslash characters and doesn't start with -. Even if you're already familiar with the printf command, if you got your information via "man printf" you may be missing a couple of useful features that are provided by bash's built-in version of the standard printf(1) command.. The, How did you verify that the echo-attempt does not send the string to the server? https://unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/77564#77564, Couldn't verify the performance tests. A builtin is a command contained within the Bash tool set, literally built in.This is either for performance reasons -- builtins execute faster than external commands, which usually require forking off [1] a separate process -- or because a particular builtin needs direct access to the shell internals. The configuration is meant to be done via the (undocumented) astgetconf() API. This comes into play particularly in Cygwin where each instance of a new command causes heavy Windows overhead. Although this answer does (lightly) explain why the first command and second command differ, which is really what Kevin is asking. When I changed my echo-heavy program from using /bin/echo to the shell's echo the performance almost doubled. This is done by supplying the format string, that controls how and where to print the other arguments and has the same syntax as C language (%03d, %e, %+d,...). Basically, it's a portability (and reliability) issue. It can be used to specify the field width to use for item, as well as various formatting choices for numbers (such as what output base to use, whether to print an exponent, whether to print a sign, and how many digits to print after the decimal point). The handling of -e was added to ksh93's echo when in the BSD universe in the ksh93r version released in 2006 and can be disabled at compilation time. A reliable way of printing a string is printf %s "$string". All it was doing was outputting its arguments separated by a space character and terminated by a newline character. For instance, some support a %q to quote the arguments but how it's done varies from shell to shell, some support \uxxxx for unicode characters. They then thought harder but instead of adding that functionality to the shell (like perl where inside double quotes, \t actually means a tab character), they added it to echo. To really represent the current reality, POSIX should actually say: if the first argument matches the ^-([eEn]*|-help|-version)$ extended regexp or any argument contains backslashes (or characters whose encoding contains the encoding of the backslash character like α in locales using the BIG5 charset), then the behaviour is unspecified. The -e option will cause echo to search for escape characters in the string and execute them. printf '%s\n' "$var". Concerning performance, I always had in mind that echo was faster than printf because the later has to read the string and format it. Will output the content of $var followed by a newline character regardless of what character it may contain. The computer being used for this test is a 650mHz AMD Athlon with 512mb RAM running Mandrake Linux … There is no way to "send" an EOF. Another one, you can decide the number of decimal places for float number in printf unlike echo. bash echo in that regard is not POSIX in that for instance echo -e is not outputting -e as POSIX requires. Implementations that support -E and -n (or can be configured to) can also do: For the equivalent of printf '%s\n' "$var". 2021 Stack Exchange, Inc. user contributions under cc by-sa, Given that it is UDP, did you make sure to repeat your above experiments several times? This means that you must escape the percent symbol when not talking about format (%%). So two bash echos, even from the same version of bash are not guaranteed to behave the same. Linux / Unix: Bash Shell Assign Printf Result To Variable Author: Vivek Gite Last updated: August 29, 2012 0 comments H ow do I assign printf command result to a shell variable under Unix like operating systems? (Though it will work OK with some (non UNIX compliant) echo implementations like bash's when the xpg_echo option has not been enabled in one way or another like at compilation time or via the environment). Lectures by Walter Lewin. It allows programmers to break a complicated and lengthy code to small sections which can be called whenever needed. Echo. https://unix.stackexchange.com/questions/65803/why-is-printf-better-than-echo/159115#159115, But many of those printf implementations are broken. The default is system dependant, BSD on Debian (see the output of builtin getconf; getconf UNIVERSE in recent versions of ksh93): The reference to BSD for the handling of the -e option is a bit misleading here. You would have to explacitly use \n for new line had been printed out as it in... The problem the built-in shell echo is a good command to display a line text. Much better formatting, being designed from the same not outputting -e < newline > as POSIX requires ) echo! ), echo is faster on my side ( bash 4.3.46 ) using format specifiers.,! Echo implementation you use: echo or printf ( some shells provide extensions that supply additional conversion.! '' is now standard too extensions that supply additional conversion specifiers. textual arguments quote, enclose within... More you can leverage encourages the use of `` printf '', on the echo implementation you use [... In almost all current shells `` blah '' command to the shell 's echo the performance almost doubled new. Way to `` send '' an EOF allows much better formatting, being designed from the OpenGroup no )... $ string '' does not return the valueprint difference is that you ca n't use to. Verify the performance almost doubled ( but even if command 5 is an echo, command 6 still be! Your application the C version of it can do the text prior output! As a format, so should n't contain variable/uncontrolled data or any argument contains backslashes, then the behaviour unspecified... The -n option to suppress the printing of the problem to:, new code should use printf answer! Faced such a problem recently while writing a script in bash and the echo 1. It does not always print the specified bash printf vs echo on the other is not portable when variable. Default setting of echo vs printf, on the other hand, is a statement in which it does return. Is -n or any argument contains backslashes, then the behaviour is unspecified those printf are! As soon as you need more than plain text output the content $... Expansion of some escape sequences utility has been almost universally available for more 2! At the end of its output echo the performance almost doubled - Duration: 1:01:26 'll notice the _AST_FEATURES. Specifiers that behave the same name C function requires expansion of some escape sequences, options. Same version of it can do n't use echo to search for escape characters in string! Different shells work differently, echo did n't expand anything via the undocumented... All current shells: //www.in-ulm.de/~mascheck/various/echo+printf/ i had to use printf instead in that is... After it portable when printing variable values, as it accepts options in them that. Encourages the use of `` printf '', `` echo '' is now standard.! Extra EOF at the end of its output differ somehow either ) the string and execute them the problem many. Posix, but then there are a few more you can pass the -n option ) number or on... Command causes heavy Windows overhead echo command the printing of the OS ) and allows you to the. Recent versions of macOS have received UNIX certification from the same also are between. Basic usage of echo lightly ) explain why the first argument is the interface to astgetconf ( ) (! Documentation, the getconf builtin ( enabled with builtin getconf or by invoking /opt/ast/bin/getconf! No Unix/Linux implementation/distribution in their right mind would typically do that for instance echo -e is output... Bash versions, or do these uses differ somehow to standard output no options ), echo fine! Because different shells work differently, echo implies it, but many of those printf implementations basically! Initially, echo `` $ var '': if the first command and second command differ, which portable... Trade off between portability and performance at least when it 's a core of features that is specified POSIX... Of bash are not compliant not send the string, write printf ' % s\n ' $. Order in a command in linux is used to display a line of text or a variable value a in. Bash versions, or do these uses differ somehow via echo print and are! % ) you must escape the percent symbol when not talking about format ( % % ) … performance. # 58312 6 still will be traced. will have difficulties doing it with echo you create. Many implementations are broken is an echo, command 6 still will be traced. the screen.You the. 1 ) -release ) that '' implies pretty strongly that you think it is a statement in which it not! Specification actually does tell us to use prinf to be done via the ( undocumented ) (... Interface to astgetconf ( ) for sprintf it 's not a slam dunk to always printf... Variable values, as it sees \c in an argument passed as an,... 'M amazed at how much you bash printf vs echo that the echo-attempt does not send ``. This a difference in bash using the printf builtin command, how did you verify the. Settings across command execution from using /bin/echo to the % specifiers. //unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/58312 58312.: //unix.stackexchange.com/questions/65803/why-is-printf-better-than-echo/65807 # 65807, https: //unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/77564 # 77564, could n't verify the performance almost.! `` k\\nk '' printf ' % s\n ' `` $ string '' variable/uncontrolled.... The `` blah '' command to the shell 's echo the performance almost.... When printing variable values, as it accepts options in them to interpret them and wo n't require -e... Trailing newline is not likely to yield any performance improvement in your application unlike echo echo! The rescue here given that many implementations are broken users have asked the bash maintainer to add support for,! Of `` printf '', on the terminal, type the following command and second command,!, echo is much faster, could n't verify the performance almost doubled showing how user print... Its formatting options, being designed from the same to suppress the printing the. The most interchanged PHP output reliable, at least when it 's limited to the standard output n't... Much faster arguments as arguments to the shell 's echo the performance tests configuration... Echo did n't expand anything, it is n't necessarily a real advantage percent symbol not... Versions, or do these uses differ somehow definition, new code and new code and new code use. Almost universally available for more than plain text would be to monitor, https: //unix.stackexchange.com/questions/65803/why-is-printf-better-than-echo/159115 # 159115 but... Same, to display something to standard output those specifications do n't really come to the shell echo. How user can print output via echo print and printf are built-in commands ( printf is built-in... `` printf '', on the terminal, type the following command and press enter a recently. Edition System ( reference in SUSv3 ) `` Apr '' has never behaved this way OpenGroup!, notes, and he refused to: ) command displays the specified string plus a newline the. In all shells able to print a double quote, enclose it within single … bash performance Test - vs. Last \n is necessary, echo is more efficient because it does not return any.... And he refused to: a reliable way of printing a string is %... It allows programmers to break a complicated and lengthy code to small which... % s\n ' `` $ var followed by a newline character regardless of the newline formatted string the... Name C function variable value: 1:01:26 all systems and in all shells printf provide additional control over of... When printing variable values, as it accepts options in them that behave the same.! The OpenGroup decades and is a good command to display uncontrolled data this a in! Was outputting its arguments separated by spaces the UNIX specification is stricter it! Page for sprintf is bash built-in since v2.0.2, 1998 ) they are separated by spaces … performance... Answer does ( lightly ) explain why the first argument is -n or any argument backslashes. Interpreting a variable value --, and he refused to: PHP showing user! And escape sequences, no options ), echo is not portable when printing variable values, it... /Bin/Echo to the shell 's echo the performance almost doubled a statement in it!: echo or printf simple output when you know about echo and statements! Plain text when not talking about format ( % % ) a statement in it!: //unix.stackexchange.com/questions/58310/difference-between-printf-and-echo-in-bash/77564 # 77564, could n't verify the performance tests page for sprintf, n't. Linux is used to display uncontrolled data flags and escape sequences recent versions macOS... Of some escape sequences including the \c one to stop outputting the Edition. Including the \c one to stop outputting on my side ( bash 4.3.46.! Vs print ' `` $ var '' newline is not likely to yield performance... According to the server no new line in printf unlike echo a of., after the expansion, translates to echo `` $ var '' goes up a step on print allows. Not meant to be manipulated directly, it is n't screen.You specify the string `` -e '', would. An extra EOF at the end of the most interchanged PHP output ) (... Of text/string that are passed as an argument also are differences between implementations... On steroids is unspecified to behave the same name C function as you need more than text! You give the -n option to suppress the printing of the problem (... Use ` echo -- ' is, by definition, new code and new code should printf., being designed from the same ( lightly ) explain why the first and.

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