37 lines
951 B
C++
37 lines
951 B
C++
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// Ben Harris
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// firstchar.cc asks for a string/word, reverses it, then forks
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// child process execls ./lastchar with the reversed string/word
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// parent process waits for ./lastchar and displays the return byte (which contains the last char of the string)
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#include <iostream>
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#include <cstdlib>
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#include <string.h>
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#include <unistd.h>
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#include <sys/types.h>
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#include <sys/wait.h>
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using namespace std;
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int main(int argc, char **argv){
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cout << "Enter a word: ";
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char word[256];
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cin.getline(word, 256);
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unsigned int input_length = strlen(word);
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char out[input_length + 1];
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unsigned int i, j;
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for(i = 0, j = input_length - 1; i < input_length; i++, j--) out[i] = word[j];
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out[input_length] = '\0';
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pid_t pid = fork();
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if(pid == 0){ // child
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execl("./lastchar", "lastchar", out, NULL);
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} else { // parent
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int status;
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wait(&status);
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cout << "First char: " << (char) WEXITSTATUS(status) << endl;
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}
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return 0;
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}
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