Well, echo sometimes does odd things on certain shells -- some expand escape sequences, some don't, some support options, some don't -- but printf "%s" "string" is pretty much guaranteed the same everywhere. If you know you'll always be using the "right" shell it doesn't really matter.
What goes wrong 1% of the time? 99% success rate is terrific for an exam, but horrible for a program.
I don't know if it'll be faster but it'll be simpler to let echo print to stdout than to redirect into &7 99 times:
Code:
exec 7>&1 # Save a copy of stdout into FD 7
exec 1>"${TEMPFILE}" # Redirect stdout into $TEMPFILE
echo a
echo b
echo c
echo d
exec 1>&7 # Restore stdout
exec 7>&-
As for logging, data belongs in stdout, human-readable errors belong in stderr, don't mix the two.
#include <stdio.h>
#include <math.h>
// this function calculates the volume of a Cylinder
int main(void)
{
int r; // radius
int h; // height
double M_PI; // pi
int pOne = pow (r, 2);
// get user input of radius and height
printf ("Enter your... (3 Replies)
I want to print a colored line using bash. I want to print:
Smtp status
where "Smtp status" will be in yellow and will be in green.
Thanks. (2 Replies)
Hi ,
I wonder if in java I can pipe the below output of the printf into a variable:
System.out.printf(" This is a test %s\n", myVariable);
I want to keep the output of the printf command to create my history array.
Thanks. (2 Replies)
#!/usr/bin/ksh
var1="Hi World"
var2="Morning"
var3=$(echo "$var1" \n "$var2")
echo $var3
var3=$(printf "$var1 \n $var2")
echo $var3
Output
Any way to get
in my $var3 ? (7 Replies)
printf "%X\n" "A"
41
printf "%X\n" "2"
2
Expected 32 (not 2).
Is there a "printf" which will output the hexadecimal value of a numeric character? (9 Replies)
This may be little confusing. I have Script1, which pulls data from the system and creates another script(lets say script2). While I run script1 I need to add printf/echo statements for script2, so that when I run script2 I see those statement.
eg: script1 765
printf " display frame-$1 timeoffset... (2 Replies)
Legends,
I want to send the output to a webpage after execution of script.
the webpage layout will be something like below
HOSTNAME at <TIME>
--------------------
ProcessName1 <some text>
ProcessName2 <some text>
.....
.....
Pls help how i will approach... (1 Reply)
Hi All;
I try to create a excel like table with headers and some fields containing values, other long and complex mathematic formulas.
I have some header like : Name Formula Value True/False
Under name column, they are some formula names, formula column some long mathematic formulas... (9 Replies)
Hello
I want to check whether certain arguments were passed to the script, and when those are, not doing a log entry.
If those arguments are not passed, always do a log entry (*new call*).
What currently i have is this:
echo "${@}"|grep -q \\- || \
tui-log -e "$LOG" "\r---- New call $$... (4 Replies)
Hello,
For some reason i dont remember, i currently believe (but beeing unsure) that printf is available on more diffrent systems (unix, bsd, linux, ??) than echo is.
Could someone please enlighten me, whether this is true or not?
Thank you
PS:
I just found pages about the diffrences of... (3 Replies)
Discussion started by: sea
3 Replies
LEARN ABOUT LINUX
guru
GURU(8) System Manager's Manual GURU(8)NAME
guru - System administration
SYNOPSIS
guru [ -e program ] [ -f ] [ -p target ]
DESCRIPTION
guru is a sophisticated program synthesis and system maintenance tool developed after midnight in numerous university computing labs. It
is based on the famous LISP Hacker system, used to develop AI programs on TENEX. guru reads a problem description from the standard input.
An innovative and occasionally correct solution is generated and written to the standard output. Typically, guru is invoked repeatedly
until an acceptable solution is generated or the user community has learned to live with the problem.
The bugreport mechanism sometimes invokes guru. In this case guru executes at a priority inversely proportional to the reported urgency of
the bug. Feature enhancements run at high priority whereas critical problems are fixed only when the machine would otherwise be idle.
If the standard input is empty, guru uses its program synthesis capabilities to generate a selection of screen editors, X widgets, compil-
ers, sundry games and the occasional diatribe.
OPTIONS -e program
New features are added to an existing program. This option should be used with caution as the enhanced program may behave unpre-
dictably or not at all.
-f Reconstructs filesystems after a crash.
-p target
Ports the entire system on which guru is executing to target, preferably a RISC machine. This is an extremely time consuming oper-
ation and is not guaranteed to terminate.
If more than one option is specified, guru may thrash. Each copy of guru has its own set of unique, additional and undocumented options.
SEE ALSO
YAPS: Yet another Program Synthesiser by S C Johnson.
NOTES
Inherent design limitations prevent guru from synthesising comments. The programs generated are undocumented. The lucidity, politeness,
relevance and language of the occasional diatribe vary considerably.
The only diagnostic is an occasional ``I deserve a raise'' - which may be ignored albeit doing so may provoke ``I resign'' - an unrecover-
able error.
Sending the output of one guru into another can produce quite startling results.
UNIX Programmer's ManualGURU(8)