65 lines
1.1 KiB
C++
65 lines
1.1 KiB
C++
#include <fcntl.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include <sys/stat.h>
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#define MAX_FILES 20
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#define BUF_SIZE 1024
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int main(int argc, char** argv)
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{
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int files[MAX_FILES] {};
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size_t file_count = 0;
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int arg = 1;
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int oflag = O_WRONLY | O_CREAT;
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if (arg < argc && strcmp(argv[arg], "-a") == 0)
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{
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oflag |= O_APPEND;
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arg++;
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}
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else
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{
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oflag |= O_TRUNC;
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}
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for (int i = arg; i < argc; i++)
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{
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files[file_count] = open(argv[i], oflag, 0644);
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if (files[file_count] == -1)
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perror(argv[i]);
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else
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file_count++;
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if (file_count >= MAX_FILES)
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{
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fprintf(stderr, "only up to %d files are supported\n", MAX_FILES);
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break;
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}
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}
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char* buffer = (char*)malloc(BUF_SIZE);
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for (;;)
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{
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ssize_t nread = read(STDIN_FILENO, buffer, BUF_SIZE);
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if (nread == -1)
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perror("stdin");
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if (nread <= 0)
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break;
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write(STDOUT_FILENO, buffer, nread);
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for (size_t i = 0; i < file_count; i++)
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write(files[i], buffer, nread);
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}
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free(buffer);
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if (ferror(stdin))
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perror("stdin");
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for (size_t i = 0; i < file_count; i++)
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close(files[i]);
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return 0;
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}
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