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#include "myproxy_common.h"
#define MAXARGS 20
pid_t
myproxy_popen(int fds[3], const char *path, ...)
{
pid_t childpid;
int p0[2], p1[2], p2[2];
assert(path);
if (access(path, X_OK) < 0) {
verror_put_string("%s not executable", path);
verror_put_errno(errno);
return -1;
}
if (pipe(p0) < 0 || pipe(p1) < 0 || pipe(p2) < 0) {
verror_put_string("pipe() failed");
verror_put_errno(errno);
return -1;
}
if ((childpid = fork()) < 0) {
verror_put_string("fork() failed");
verror_put_errno(errno);
return -1;
}
if (childpid == 0) { /* child */
va_list ap;
const char *argv[MAXARGS];
int i=0;
close(p0[1]); close(p1[0]); close(p2[0]);
if (dup2(p0[0], 0) < 0 ||
dup2(p1[1], 1) < 0 ||
dup2(p2[1], 2) < 0) {
perror("dup2");
exit(1);
}
argv[i++] = path;
va_start(ap, path);
while ((argv[i++] = va_arg(ap, const char *)) != NULL) {
assert(i < MAXARGS);
}
va_end(ap);
execv(path, (char *const *)argv);
fprintf(stderr, "failed to run %s: %s\n", path, strerror(errno));
exit(1);
}
close(p0[0]); close(p1[1]); close(p2[1]);
fds[0] = p0[1];
fds[1] = p1[0];
fds[2] = p2[0];
return childpid;
}
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