Exemple #1
0
static int pipelineExecProc(struct pipeline* pl, struct plProc *proc,
                            int prevStdoutFd, int stdinFd, int stdoutFd, int stderrFd,
                            void *otherEndBuf, size_t otherEndBufSize)
/* start a process in the pipeline, return the stdout fd of the process */
{
/* determine stdin/stdout to use */
int procStdinFd, procStdoutFd;
if (proc == pl->procs)
    procStdinFd = stdinFd; /* first process in pipeline */
else
    procStdinFd = prevStdoutFd;
if (proc->next == NULL)
    procStdoutFd = stdoutFd; /* last process in pipeline */
else
    prevStdoutFd = pipeCreate(&procStdoutFd);

/* start process */
if ((proc->pid = fork()) < 0)
    errnoAbort("can't fork");
if (proc->pid == 0)
    {
    if (otherEndBuf != NULL)
        plProcMemWrite(proc, procStdoutFd, stderrFd, otherEndBuf, otherEndBufSize);
    else
        plProcExecChild(proc, procStdinFd, procStdoutFd, stderrFd);
    }

/* don't leave intermediate pipes open in parent */
if (proc != pl->procs)
    safeClose(&procStdinFd);
if (proc->next != NULL)
    safeClose(&procStdoutFd);
return prevStdoutFd;
}
Exemple #2
0
static void execProcChild(struct pipeline* pl, struct plProc *proc,
                          int procStdinFd, int procStdoutFd, int stderrFd,
                          void *otherEndBuf, size_t otherEndBufSize)
/* handle child process setup after fork.  This does not return */
{
if (otherEndBuf != NULL)
    plProcMemWrite(proc, procStdoutFd, stderrFd, otherEndBuf, otherEndBufSize);
else
    plProcExecChild(proc, procStdinFd, procStdoutFd, stderrFd);
}