Re: [netcf-devel] [PATCH] Capture stdout and stderr when execing external programs

This is in response to: https://bugzilla.redhat.com/show_bug.cgi?id=616060 but will also be useful in an upcoming patch which needs to retrieve the output of /etc/rc.d/init.d/netcf-transaction. Before forking, we now create a pipe, then after forking, the child dup2's both stdout and stderr to the write side of the pipe, and the parent calls fdopen() on the read side of the pipe and then calls gnulib's fread_file() before calling waitpid() to reap the process. --- src/dutil_linux.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++---- src/dutil_linux.h | 2 +- 2 files changed, 72 insertions(+), 7 deletions(-)

@@ -133,6 +153,18 @@ exec_program(struct netcf *ncf, _exit(1); } + if (pipeout[1] >= 0) { + /* direct stdout and stderr to the pipe */ + if (dup2(pipeout[1], fileno(stdout)) < 0 + || dup2(pipeout[1], fileno(stderr)) < 0) { + /* don't report_error, as it will never be seen anyway */ + _exit(1);