C external execution - trap stdout + stderr

[ChokSheak Lau]

Hi,

using popen() doesn't seem to give me any way to capture
the stderr of the child process.

does anyone know whether there is any way to capture these:
1. stdout
2. stderr
3. exitcode

and return to the calling C program after execution?
you can assume a Linux or Unix like system.

any response or insight would be appreciated. Thanks.

chok

 

[Ben Pfaff]

using popen() doesn't seem to give me any way to capture
the stderr of the child process.

Your question is outside the domain of comp.lang.c, which discusses
only the standard C programming language, including the standard C
library. This is a remarkably narrow topic compared to what many
people expect.

For your convenience, the list below contains topics that are not
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[SM Ryan]

# Hi,
#
# using popen() doesn't seem to give me any way to capture
# the stderr of the child process.
#
# does anyone know whether there is any way to capture these:
# 1. stdout
# 2. stderr

To do anything more elaborate with these, you'll probably end up learning
how to use pipe(), exec...(), and fork().

# 3. exitcode

pclose() returns this.

 

[Keith Thompson]

# Hi,
#
# using popen() doesn't seem to give me any way to capture
# the stderr of the child process.
#
# does anyone know whether there is any way to capture these:
# 1. stdout
# 2. stderr

To do anything more elaborate with these, you'll probably end up learning
how to use pipe(), exec...(), and fork().

# 3. exitcode

pclose() returns this.

Please use the conventional "> " prefix for quoted text.
Please use the standard "-- " signature delimiter.

I'm curious -- why do you persist in using your non-standard
formatting when you've been told repeatedly that it causes real
problems?

popen(), pipe(), exec...(), fork(), and pclose() are all non-standard
functions, not defined by the C standard. comp.unix.programmer is a
good place to discuss them. comp.lang.c is not.

 

[CBFalconer]

.... snip ...

Please use the conventional "> " prefix for quoted text.
Please use the standard "-- " signature delimiter.

I'm curious -- why do you persist in using your non-standard
formatting when you've been told repeatedly that it causes real
problems?

He apparently doesn't care what troubles he causes for others.
The recommended solution is PLONKing.