I was reading Kernighan Ritchie book chapter 4 which deals with character pointers.I am not able to understand following different type of declarations
Code:
char aname[][15] = { "Illegal month", "Jan", "Feb", "Mar" };
char amessage[] = "now is the time";
[code]...
I wonder why arrays in the C programming language are pointers to the first element of the array, not the first element of the array itself?
View 14 Replies View Related1.What character instructd the shell to interpret a special character as an ordinary character?
2.What directory contains some of the utilities available on the system in the form of binary files?
3. What command is used to search the location of a utility?
4. What command is used to instruct the editor to write the file and quit the editor?
5. What key quits the more utility and displays the shell prompt?
6. What command starts a child shell as the super user, taking on root's identity and environment?
7. Which wildcard characters can be used for searching all the files in the system that start with "A"?
8. The user name or login name of the super user is????
[Code]....
I have a problem on a program,the problem take a very long time when i try to add two big arrays element by elementI know that matlab make adding vectors more faster than adding element by element but I don't know how!!!do any body knew how matlab make vectors operations more faster than element by element???I want to make my calculation more faster because the program is very big
View 8 Replies View Relatedneed to process files within multiple directories and transfer these to a remote server. What I had in mind was to use arrays for this; code pasted below (explains it better):
Code:
#set the arrays
array_A=( fileA* pathtodestA hostA passwordA )
[code]...
Does diff not like arrays? How do achieve the following?
Code:
stuart@stuart:~/music transfer$ diff file1.txt file2.txt
1c1
< bonkers_in_phoenix.mp3
[code]....
I'm making script for automated compiling of one program which would output builds optimized for many architectures. For clearancy, I do each build in it's own catalogue and list of builds with their respective catalogues would be stored as array. I'm using this guide as reference. It describes making array as naming a variable with additional brackets denoting it's position in array.
In my code, it looks exactly like this:
Code:
mtune[1]="build/mtune/athlon"
mtune[2]="build/mtune/athlon-4"
mtune[3]="build/mtune/athlon-mp"
[code]....
But upon invoking $mtune or any $mtune[x] variable, output is blank, like the variable(s) were never initialized. What am I doing wrong?
I have a Perl script that has two arrays - they are related. I would like to print out the contents into two columns next to each other.
#!/usr/bin/perl
open(PINGFILE, </home/casper/pingdata.txt") or die " can not open file ";
my @totalfile=<PINGFILE>;
foreach $string(@totalfile) {
if ($string =~ m/(^1sping)(?=.*max))/) {
push(usecstring,"$string");
[Code]...
I am working on a project that needs to use structures and I'm pretty sure string arrays. First I declare my structures and they must be exactly like this.
typedef struct
{
int hour;
[code]....
I'm trying to figure how to create an small array of 3x3 arrays such I can do
Code:
SUM1(i) = SUM1(i) + SUM2
where i goes from 1 to 8 and SUM2 is a 3x3 array.
a project using bluetooth to send data byte by byte to external devices buti'm not familiar using arrays to read file from another location before sending the data.If you could,do correct my codes.Here's my code,
void loop(){
char Msg[]={"Hello"};
char *start;
[code]...
I have something like this:
$arr_hash{'produce'}{'veggies'}[0] = Broccoli
$arr_hash{'produce'}{'veggies'}[1] = Cauliflower
$arr_hash{'produce'}{'veggies'}[2] = Carrots
[code]...
I'm trying to figure out how to code for this specific type of instance - I want to use a hash and have the key be a reference to an array, and not use the key in the standard way of it being a scalar. Basically, I have a large output that I need to process line by line, and rather have access to it as an array than a big block in a scalar. For the big block hash as a scalar I would do -
Code:
foreach $CONTROLLER (<CONTROLLER_LIST>) {
$ALL_DISKS{$CONTROLLER} = `ssh -n <commands>`;
}
Now I know I could take the scalar and split it to another array after the fact like -
Code:
@TEMP_HOLD = split (/s+/,$ALL_DISKS{$CONTROLLER});
How would I code it that I would have access to the key information as an array and not a scalar? I know it needs to be a pointer and we're going to have -> in there somewhere, but not sure how to approach it. Some of the documentaiton I've been reading about referencing I've found a little confusing so far, and trying to figure out how to use them in context of what I'm working on.
I'm writing a code to get the index of the last occurrence of a given substring in a string.
Code:
int StringHandler::lastIndexOf(string src, const string s) {
unsigned int lastIndex = string::npos;
if (src.find(s, 0) == string::npos) {
return -1; } else {
bool isLast = false; unsigned int i = 0; do {
lastIndex = src.find(s, i);
if (lastIndex != string::npos) { i = lastIndex + 1;
if (i == src.size()) { isLast = true;
} } else { isLast = true;
} } while (!isLast);
} return lastIndex;
}
My problem is: execution steps into an if with a false condition! Check the values of i and src.size() at the right panel. How could be possible for the program to run the highlighted statement? The if condition above is false! [URL]. I could use char arrays, for example, but this kind of false validation has happened to me more than once, I'm using G++ 4.5 with these flags: -O0 -g -Wall -c
I just started programming in PHP so I haven't figured out how to do this yet, but I have a multi-dimensional array that I need to sort by one column. That's fine...but I need the sort to ignore case! Right now I have it sorted by 'name' (the other column is 'uid').
The problem is that by the default the sort is case-sensitive so the array looks like this:
Code:
Apple 4015
Banana 4011
Cherry 4045
avocado 4046
I want to be able to sort the the 'name' column in a case-insensitive manner so that the array actually looks like:
Code:
Apple 4015
avocado 4046
Banana 4011
Cherry 4045
How to accomplish this? Just FYI I'm not actually sorting the PLUs for fruits...but it was a simple example. I'm actually doing this for a Facebook application.
I would like to combine two arrays and delete duplicates that might occur. I tried to solve it like this:
Code:
combined=( "${results1[@]}" "${results2[@]}" )
printf "${combined[@]}" | sort -n | uniq
Example:
result1 (4 elements):
[Code]....
In my code printf seems to have a problem with elements that have the same letters but a space inbetween. For instance "new foo", "newfoo" are the same for printf
I've got a situation. I'm having GNU bash version 3.00.16(1) on Solaris 10. I need to declare an array say arr1 which will be populated by an output of a command.
declare -a arr1
arr1=( $(/some/command) )
Supposing it will eventually (after executing the command) have element values as -
arr1[0]=1234
arr1[1]=5678
arr1[2]=7890
Now, I need to declare another set of arrays, one for each of the element values above - e.g.
declare -a arr1_1234
declare -a arr1_5678
declare -a arr1_7890
And I also need to populate elements of each of above 3 arrays with output of another command in a loop. So, these arrays will hold values something like -
arr1_1234[0]="abc"
arr1_1234[1]="def"
arr1_1234[2]="ghi"
arr1_5678[0]="jkl"
arr1_5678[1]="mno"
arr1_5678[2]="pqr"
arr1_7890[0]="tuv"
arr1_7890[1]="xyz"
arr1_7890[2]="aab"
I'm able to declare and populate arr1[*]. My question is how do I declare, populate and print the subsequent arrays and their elements?I am feeling rather thick to get this working.
I am curious if there is a way to describe and use variable sized multi-dimensional arrays in C using pointers. I mean, for 1-dimensional array e.g. I can use the following piece of code:
...
int i , N;
int *array;
scanf("%d", &N);
array = (int*) malloc(N*sizeof(int));
for (i=0; i<N; ++i) array[i] = i; // Assigning values to the array
for (i=0; i<N; ++i) printf("%d ", array[i]); // Printing the assigned values
free (array);
...
But what about the two dimensional array[N][M] ? I guess I have to use a double pointer e.g: int **array. But how exactly? Note that I use C90 and not C99.
i'm getting an undefined offset for the associative arrays [28-46] in this format.
[Code]....
i have read that i can prevent the notices by doing the following, but it's not working for me
PHP Code:
[Code]....
I have a problem with arrays in awk. What i want is to take some data from a file (ssh log) and print it to a html table. I have managed to print some stuff (user logged in and how many times they have logged in) What i want more is to take all the ip that each user logged in from and print it in a row next to the username and times (in the code i typed blabbla where i want the ip to be shown. How do you think i should approch that, multidimensional arrys maybe?
Code:
I have a string like this "/home/test/filename.txt" and i want to delete all character after the last "/". how to do that using sed or awk.
View 5 Replies View Relatedi am compiling the following program in linux. it's in c language. after the compilation with gcc when i run the executable file. it asks for input. but when i enter a name. i prints "Segmentation fault" and then terminate the program. can you please help me.
#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>
#include <unistd.h>
[code]....
which is the simplest way to have first and last character cropped out from a string? Something simpler than
Code:
echo $STRING | cut -b 2- | rev | cut -b 2- | rev
I have the following file:
Code:
1 line
...
49 test test=AA:AA:AA:AA:AA=0
I need to substitute on the line number 49, all text until =. I have used the following, but with no actual result.
sed -re '49s/^.+=//' file
and
sed -e '49s/.*[=]//' file
I have a file with one line. I want to check whether the first character is TAB or space, how can i do this.? using "cut" wont as it "bypasses the tab and space characters"
View 3 Replies View RelatedI am trying to check if the 9th character in a file on each line is a v and if so, then print the first word. I've tried a number of variations and am stuck !If it's possible to also check if character position 1 begins with a s in the same awk, that would make it cleaner instead of using egrep.
egrep '^s' file | nawk '{virtual=substr($0,9,1); if ($virtual=="v") {printf "%s", $1}}'
nawk: illegal field $(e)
input record number 1
source line number 1
I believe I have unwanted ' characters left in a 9 element character array that are causing subsequent operations with it to fail. I see wildly differing views on the web on the proper way to flush 'em. It's clearly not as simple as it would appear at first sight. What's currently the best (or else "least deprecated") method?
View 5 Replies View RelatedI am loading variables for cXtXdXsX disk names into a script, and at present I have only accounted for there being 3 characters from c to t. I need to change it to a variable recognition so that it can count any number of charcters such as c1t , c10t , or c100t.
I can then take that information and use it with the following string to strip off the lead characters so as to make the 3 in $substr either a variable or redirect to multiple occurrences of raw based on the count returned.
sub raw {
$substr = substr ($_, 3);
$raw1 = substr ($substr, 0, -4);
$raw = lc($raw1);
}
how to count from the c to the t inclusive so I get 3, 4, 5, etc ...
how to replace last character string. For example
$>export T1=abcde
$>export T2=xyz
how to get result abcdxyz?
I have a string as below
LogFormat "%h %l %u %t "%r" %>s %b "%{Referer}i" "%{User-Agent}i"" combined
Want the above string to be modified as
LogFormat "%h %l %u %D %t "%r" %>s %b "%{Referer}i" "%{User-Agent}i"" combined
inserting %D after %u in the string