${parameter/pattern/string}
The pattern is expanded to produce a pattern just as in filename expansion. Parameter
is expanded and the longest match of pattern against its value is replaced with string.
If pattern begins with ‘/', all matches of pattern are replaced with string. Normally only
the first match is replaced. If pattern begins with ‘#', it must match at the beginning of
the expanded value of parameter. If pattern begins with ‘%', it must match at the end of
the expanded value of parameter. If string is null, matches of pattern are deleted and the
/ following pattern may be omitted. If parameter is ‘@' or ‘*', the substitution operation is
applied to each positional parameter in turn, and the expansion is the resultant list. If
parameter is an array variable subscripted with ‘@' or ‘*', the substitution operation is
applied to each member of the array in turn, and the expansion is the resultant list.
And BTW, just because you see characters representing a number does not mean it is an integer, (or float).
In the case of bash everything is a string and bash decides how to interpret strings according to how you code for them.
Example:-
hi, im trying to compare two variables in csh to put in an if statement, eg:
set a = $firstnum
set b = $secondnum
if ($a -ge $b) echo $a
But I get an error ("if: Expression syntax"). How can I make csh see my variables as integers?
thanks in advance! (5 Replies)
I'm trying to write an integer to a file using the write() function, but write() requires the parameter to be written to be a const void*.
How would I go about doing this?
also: using itoa() produces a " warning: implicit declaration of function 'itoa' " even though i have #included stdlib.h (2 Replies)
Hi,
When I compare currentfiledate to reportfiledate I get a "-bash:
currentfiledate=20090220080101
reportfiledate=20090219231245
if ; then
echo -ne "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! \n"
echo -ne "!! Running the load utility !! \n"
fi
Our... (15 Replies)
I would like to add 4.7 and 1.2. However I am unable to do this with expr.
Any simple ideas (even using something other than expr)?
Example:
me> expr 4 + 1
5
me> expr 4.7 + 1.2
expr: 0402-046 A specified operator requires numeric parameters. (18 Replies)
Hi, I need a script that will:
1. Go through about 20 different folders, each containing about 20 1d files. The 1d files go something like this:
22.253 37.707 78.117 112.374 127.944 156.067 180.956 233.785 249.256 ... (1 Reply)
Wonderful evening to all of you!
My problem has to possible starting points.
Well, not really, but getting to either one is no problem at all.
So i got either a string in the format of "1920x1080" or simply the integers X = 1920 and Y = 1080.
When I am done, I would like to have an output... (5 Replies)
Hi,
I am working in bash in Mac OSX, I have following 'input.txt' file:
<INFO> HypoTestTool: >>> Done running HypoTestInverter on the workspace combined
<INFO> HypoTestTool: The computed upper limit is: 11 +/- 1.02651
<INFO> HypoTestTool: expected limit (median) 11
<INFO> HypoTestTool: ... (13 Replies)
Hi,
I'm totally new at this, so help will be appreciated.
I have a directory with a bunch of files in it. The files are named xinteger_yinteger_zinteger.vtk (eg, x3_y0_z-1.vtk). I want to read the filenames and then assign the integers to variables that I then can use in expressions. So, for... (6 Replies)
Hi,
I can't figure out what I'm missing. I'm running a query to see if there are any streams recording on my DVR before starting a scripted update. I'm guessing that it is viewing $VIDEO as a string instead of an int. I've tried everything I saw on google but it still comes back as $VIDEO is... (8 Replies)
Hi,
I am new in bash scripting. In my work, I provide support to several users and when I connect to their computers I use the same admin and password, so I am trying to create a script that will only ask me for the IP address and then connect to the computer without having me to type the user... (5 Replies)
Discussion started by: arcoa05
5 Replies
LEARN ABOUT LINUX
rbash
RBASH(1) General Commands Manual RBASH(1)NAME
rbash - restricted bash, see bash(1)RESTRICTED SHELL
If bash is started with the name rbash, or the -r option is supplied at invocation, the shell becomes restricted. A restricted shell is
used to set up an environment more controlled than the standard shell. It behaves identically to bash with the exception that the follow-
ing are disallowed or not performed:
o changing directories with cd
o setting or unsetting the values of SHELL, PATH, ENV, or BASH_ENV
o specifying command names containing /
o specifying a file name containing a / as an argument to the . builtin command
o specifying a filename containing a slash as an argument to the -p option to the hash builtin command
o importing function definitions from the shell environment at startup
o parsing the value of SHELLOPTS from the shell environment at startup
o redirecting output using the >, >|, <>, >&, &>, and >> redirection operators
o using the exec builtin command to replace the shell with another command
o adding or deleting builtin commands with the -f and -d options to the enable builtin command
o using the enable builtin command to enable disabled shell builtins
o specifying the -p option to the command builtin command
o turning off restricted mode with set +r or set +o restricted.
These restrictions are enforced after any startup files are read.
When a command that is found to be a shell script is executed, rbash turns off any restrictions in the shell spawned to execute the script.
SEE ALSO bash(1)GNU Bash-4.0 2004 Apr 20 RBASH(1)