How to detect an error at the beginning of a pipeline?
In my script I need to work with the exit status of the non-last command of a pipeline:
do_real_work 2>&1 | tee real_work.log
To my surprise, $? contains the exit code of the tee. Indeed, the following command:
false 2>&1 | tee /dev/null ; echo $?
outputs 0. Surprise, because the csh's (almost) equivalent
false |& tee /dev/null ; echo $status
prints 1.
How do I get the exit code of the non-last command of the most recent pipeline?
sh pipeline
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
add a comment |
In my script I need to work with the exit status of the non-last command of a pipeline:
do_real_work 2>&1 | tee real_work.log
To my surprise, $? contains the exit code of the tee. Indeed, the following command:
false 2>&1 | tee /dev/null ; echo $?
outputs 0. Surprise, because the csh's (almost) equivalent
false |& tee /dev/null ; echo $status
prints 1.
How do I get the exit code of the non-last command of the most recent pipeline?
sh pipeline
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
add a comment |
In my script I need to work with the exit status of the non-last command of a pipeline:
do_real_work 2>&1 | tee real_work.log
To my surprise, $? contains the exit code of the tee. Indeed, the following command:
false 2>&1 | tee /dev/null ; echo $?
outputs 0. Surprise, because the csh's (almost) equivalent
false |& tee /dev/null ; echo $status
prints 1.
How do I get the exit code of the non-last command of the most recent pipeline?
sh pipeline
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
In my script I need to work with the exit status of the non-last command of a pipeline:
do_real_work 2>&1 | tee real_work.log
To my surprise, $? contains the exit code of the tee. Indeed, the following command:
false 2>&1 | tee /dev/null ; echo $?
outputs 0. Surprise, because the csh's (almost) equivalent
false |& tee /dev/null ; echo $status
prints 1.
How do I get the exit code of the non-last command of the most recent pipeline?
sh pipeline
sh pipeline
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
asked Nov 15 '18 at 0:14
Mikhail T.Mikhail T.
1,0271330
1,0271330
add a comment |
add a comment |
1 Answer
1
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Bash has set -o pipefail which uses the first non-zero exit code (if any) as the exit code of a pipeline.
POSIX shell doesn't have such a feature AFAIK. You could work around that with a different approach:
tail -F -n0 real_work.log &
do_real_work > real_work.log 2>&1
kill $!
That is, start following the as yet non-existing file before running the command, and kill the process after running the command.
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
add a comment |
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1 Answer
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active
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Bash has set -o pipefail which uses the first non-zero exit code (if any) as the exit code of a pipeline.
POSIX shell doesn't have such a feature AFAIK. You could work around that with a different approach:
tail -F -n0 real_work.log &
do_real_work > real_work.log 2>&1
kill $!
That is, start following the as yet non-existing file before running the command, and kill the process after running the command.
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
add a comment |
Bash has set -o pipefail which uses the first non-zero exit code (if any) as the exit code of a pipeline.
POSIX shell doesn't have such a feature AFAIK. You could work around that with a different approach:
tail -F -n0 real_work.log &
do_real_work > real_work.log 2>&1
kill $!
That is, start following the as yet non-existing file before running the command, and kill the process after running the command.
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
add a comment |
Bash has set -o pipefail which uses the first non-zero exit code (if any) as the exit code of a pipeline.
POSIX shell doesn't have such a feature AFAIK. You could work around that with a different approach:
tail -F -n0 real_work.log &
do_real_work > real_work.log 2>&1
kill $!
That is, start following the as yet non-existing file before running the command, and kill the process after running the command.
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
Bash has set -o pipefail which uses the first non-zero exit code (if any) as the exit code of a pipeline.
POSIX shell doesn't have such a feature AFAIK. You could work around that with a different approach:
tail -F -n0 real_work.log &
do_real_work > real_work.log 2>&1
kill $!
That is, start following the as yet non-existing file before running the command, and kill the process after running the command.
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
answered Nov 15 '18 at 0:35
l0b0l0b0
34.8k1587151
34.8k1587151
add a comment |
add a comment |
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