Two options:

1. set the pipefail option from ksh (set -o pipefail), then the exit status of a pipeline will be that of the right-most pipeline component that failed.

   set -o pipefail
   if ! A | B | C; then
     echo at least one of the commands failed.
   fi
   

2. look for non-zero values in $pipestatus. With the extendedglob option enabled, $pipestatus[(r)^0] (or $pipestatus[(r)<1->] which doesn't require extendedglob) will return the exit status of the left-most failing pipeline component and $pipestatus[(R)^0] of the right-most, so you can do:

   set -o extendedglob
   A | B | C
   if (( $pipestatus[(r)^0] )); then
     echo at least one of the commands failed.
   fi
   

   or

   A | B | C
   if (( $pipestatus[(r)<1->] )); then
     echo at least one of the commands failed.
   fi
   

   With the I subscript flag instead of r/R, you'll get the Index of the right-most matching element, so you can do:

   A | B | C
   if (( failed = $pipestatus[(I)<1->] )); then
     echo component $failed failed.
   fi
   

Two options:

1. set the pipefail option from ksh (set -o pipefail), then the exit status of a pipeline will be that of the right-most pipeline component that failed.

   set -o pipefail
   if ! A | B | C; then
     echo at least one of the commands failed.
   fi
   

2. look for non-zero values in $pipestatus. With the extendedglob option enabled, $pipestatus[(r)^0] (or $pipestatus[(r)<1->] which doesn't require extendedglob) will return the exit status of the left-most failing pipeline component and $pipestatus[(R)^0] of the right-most, so you can do:

   set -o extendedglob
   A | B | C
   if (( $pipestatus[(r)^0] )); then
     echo at least one of the commands failed.
   fi
   

   or

   A | B | C
   if (( $pipestatus[(r)<1->] )); then
     echo at least one of the commands failed.
   fi
   

   With the I subscript flag instead of r/R, you'll get the Index of the right-most matching element, so you can do:

   A | B | C
   if (( failed = $pipestatus[(I)<1->] )); then
     echo component $failed failed.
   fi
   

   ${pipestatus:#0} will expand to the components of $pipestatus except 0, so you could also do:

   A | B | C
   failed_statuses=( ${pipestatus:#0} )
   if (( $#failed_statuses )); then
     echo "${#failed_statuses} command(s) failed. Statuses: $failed_statuses"
   fi
   

Two options:

1. set the pipefail option from ksh (set -o pipefail), then the exit status of a pipeline will be that of the left-most pipeline component that failed.

   set -o pipefail
   if ! A | B | C; then
     echo at least one of the commands failed.
   fi
   

2. look for non-zero values in $pipestatus. With the extendedglob option enabled, $pipestatus[(r)^0] (or $pipestatus[(r)<1->] which doesn't require extendedglob) will return the exit status of the left-most failing pipeline component and $pipestatus[(R)^0] of the right-most, so you can do:

   set -o extendedglob
   A | B | C
   if (( $pipestatus[(r)^0] )); then
     echo at least one of the commands failed.
   fi
   

   or

   A | B | C
   if (( $pipestatus[(r)<1->] )); then
     echo at least one of the commands failed.
   fi
   

Two options:

1. set the pipefail option from ksh (set -o pipefail), then the exit status of a pipeline will be that of the right-most pipeline component that failed.

   set -o pipefail
   if ! A | B | C; then
     echo at least one of the commands failed.
   fi
   

2. look for non-zero values in $pipestatus. With the extendedglob option enabled, $pipestatus[(r)^0] (or $pipestatus[(r)<1->] which doesn't require extendedglob) will return the exit status of the left-most failing pipeline component and $pipestatus[(R)^0] of the right-most, so you can do:

   set -o extendedglob
   A | B | C
   if (( $pipestatus[(r)^0] )); then
     echo at least one of the commands failed.
   fi
   

   or

   A | B | C
   if (( $pipestatus[(r)<1->] )); then
     echo at least one of the commands failed.
   fi
   

   With the I subscript flag instead of r/R, you'll get the Index of the right-most matching element, so you can do:

   A | B | C
   if (( failed = $pipestatus[(I)<1->] )); then
     echo component $failed failed.
   fi