58 lines
1.3 KiB
C
58 lines
1.3 KiB
C
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/* This file is part of the sample code and exercises
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* used by the class "Advanced Programming in the UNIX
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* Environment" taught by Jan Schaumann
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* <jschauma@netmeister.org> at Stevens Institute of
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* Technology.
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*
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* This file is in the public domain.
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*
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* You don't have to, but if you feel like
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* acknowledging where you got this code, you may
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* reference me by name, email address, or point
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* people to the course website:
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* https://stevens.netmeister.org/631/
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*/
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/*
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* Stripped down version of 'cat', using unbuffered I/O.
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* ./simple-cat < simple-cat.c
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*
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* Guess what, this is also a primitive version of 'cp':
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* ./simple-cat <simple-cat.c >simple-cat.copy
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*/
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#include <errno.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#ifndef BUFFSIZE
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#define BUFFSIZE 32768
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#endif
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int
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main(int argc, char **argv) {
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int n;
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char buf[BUFFSIZE];
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/* cast to void to silence compiler warnings */
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(void)argc;
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(void)argv;
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while ((n = read(STDIN_FILENO, buf, BUFFSIZE)) > 0) {
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if (write(STDOUT_FILENO, buf, n) != n) {
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fprintf(stderr, "Unable to write: %s\n",
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strerror(errno));
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exit(EXIT_FAILURE);
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}
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}
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if (n < 0) {
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fprintf(stderr, "Unable to read: %s\n", strerror(errno));
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exit(EXIT_FAILURE);
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}
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return(EXIT_SUCCESS);
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}
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