ch                 95 kernel/pipe.c        char ch;
ch                 96 kernel/pipe.c        if (copyin(pr->pagetable, pr->sz, &ch, addr + i, 1) == -1) {
ch                101 kernel/pipe.c        pi->data[pi->nwrite++ % PIPESIZE] = ch;
ch                116 kernel/pipe.c    char ch;
ch                132 kernel/pipe.c      ch = pi->data[pi->nread % PIPESIZE];
ch                133 kernel/pipe.c      if (copyout(pr->pagetable, pr->sz, addr + i, &ch, 1) == -1) {