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/* Example of how to handle stdin redirect
*
* The problem is non-trivial since Linux epoll, which libuEv uses, does
* not support I/O watchers for regular files or directories.
*
* This works:
* echo foo | redirect
* This doesn't:
* redirect < foo.txt
*
* However, with a little bit of hacking libuEv can be made to handle
* reading from stdin as a special case.
*/
#include <err.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include "src/uev.h"
void process_stdin(uev_t *w, void *arg, int events)
{
char buf[256];
int len;
if (UEV_ERROR == events) {
warnx("Spurious problem with the stdin watcher, restarting.");
uev_io_start(w);
}
len = read(w->fd, buf, sizeof(buf));
if (len == -1) {
warn("Error reading from stdin");
return;
}
if (len == 0 || UEV_HUP == events) {
warnx("Connection closed.");
return;
}
printf("Read %d bytes\n", len);
if (write(STDOUT_FILENO, buf, len) != len)
warn("Failed writing to stdout");
}
int main(int argc, char **argv)
{
uev_ctx_t ctx;
uev_t watcher;
int ret;
uev_init(&ctx);
ret = uev_io_init(&ctx, &watcher, process_stdin, NULL, STDIN_FILENO, UEV_READ);
if (ret)
err(errno, "Failed setting up STDIN watcher");
return uev_run(&ctx, 0);
}
/**
* Local Variables:
* compile-command: "make redirect; echo hej > hej.txt; ./redirect < hej.txt"
* indent-tabs-mode: t
* c-file-style: "linux"
* End:
*/
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