How to remove alternate char from file using shell script? If the file content is "1234567890" the output file should be "24680".
sed 's/(.)(.)/2/g' filename
Now there may be small modification to generate two alternate byte, what it should be? If the file content is "1234567890" the output file should be "125689".
With this I may remove the last emtpy char which is not visible, coming from net, windows, ...
Code:
echo "$mystringwindowsorotherwithemptylastchar" |sed s/.$//
However if there are not then it makes a problem and delete effectively an existing char.
Code:
echo "klklj" |sed s/.$//
klkl
Anyone would have a solution for SH?
I've never programed shell scripting.
Code goes like so:
I simply want to read a file "data.txt" line by line Then char by char and add them into a result var. The file is supossed to always contain numeric values
m getting the following error when trying to compile:Quote:
$ make
g++ -march=athlon64 -O2 -pipe -fomit-frame-pointer -msse3 -c -D_GNU_SOURCE -DPLUGIN_NAME_I18N='"undelete"' -DHAVE_SVDRP -I../../../include undelete.c
[code]...
Programming in C.I have two char arrays.char buf1[1024];char buf2[1024];Aren't buf1 and buf2 also pointers?I read in 1024 bytes into buf1 which contain about 300 bytes of characters with newlines. The data is basically a few English sentences. I'm trying to scan buf1 for newlines and then stop at the 1st newline and copy the rest of the data from that 1st newline into buf2.So I run a for loop to look for that new line.
Code:
for(i=0; i<1024;i++) {
if((strcmp(&buf1[i], "
[code]...
I am having trouble with the following exception class.
Code:
/**Standard Exception
*
*@description
*@update
*@changes
[code]....
Line 43 points at the snprintf() command.I think the error has to do with the function being virtual and the const after the function definition, however although I have been looking really hard I have not being able to find the reason nor the solution to the problem.
One workaround that I know is moving the block of source withing the virtual function, in the constructor, however having read around (boost library exceptions tutorials) it specifically said that formating of errors messages should not take place withing the construction of objects because we are risking throwing an exceptions and messing up the flow order.
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Code:
int main(int argc, char *argv[])
{
[code]....
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For one character, it semi-works...it'll decrypt it fine, but it'll return it as it's ASCII value (i.e.: if I encrypt "A", it'll decrypt it as 65). Which, I can easily just do sprintf(decrypted_buffer, "%c", 65) for example and be fine. But, when I'm sending text bigger than one character, the encryption for AB gives me something like 1061043 after running the decrypting xor on it.
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Code:
/**
* str2mpz()
* b The current buffer of text to convert [in]
* m The mpz_t variable to store converted text [out]
[code]....
I have a char*[] array:
Code:
char* myarray[] = {"Hello", "there!", "LQ"};
and I wish to use/ write a function to find the number of elements in myarray (in this case, its 3).
*equivalent of .NET's array.size() that returns number of elements in array
How do I achieve it?
Below I've presented the declaration, definition and the calling method of a function w.r.t pass by reference:
Declaration
Code:
void getUnpackedMsg (unsigned char &data, unsigned int numberOfBits);
Definition
line 278: Shown in RED
Code:
void packedMessage :: getUnpackedMsg (unsigned char &emptyArray, unsigned int numberOfBits)
{
...
...
printf ("
[code].....
What could be a command to erase from the cursor up to the first non-blank char in vi (or vim)?
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Code:
#include<unistd.h>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
[code].....
I am a dummy in C programming. I have a problem with copying the array of 64 elements of unsigned char to array of 8 element of uint64_t. For example:
unsigned char p[64]
uint64_t Data[8];
memcpy (&Data, &p, 64);
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This works for "char" but i need "char*",how do I do it?
Code:
char* tk = (char*) calloc(ctk+1,sizeof(char*));
Error when I use it:
Code:
error: invalid conversion from har* to har
I would like to create a small C tool. I encounter a problem of how to make a function to check an input chars contains numbers (started from the second element).
Some samples:
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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;
}
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I've got a strange bug that I cannot figure out how to solve. Here is the function.
Code:
int getnexttab(char input[], int index, int length)
{
[code]....
Please look at the comments
Code:
/*
* TEST CASE TO CHECK DIFFERENCES BETWEEN STRING AS
[code]...
I have the following char* array
Code:
char* chrarray[] = {"Hello","LinuxQuestions"};
and I need to pass it into a function, how should I define my function in the header file?
[code]....
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I'm using the following code:
Code:
But it returns me
Code: