In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 9:
prefix=/usr
^----^ SC2034 (warning): prefix appears unused. Verify use (or export if used externally).


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 10:
exec_prefix=/usr
^---------^ SC2034 (warning): exec_prefix appears unused. Verify use (or export if used externally).


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 19:
[ -r ${SYSCONFIG_DIR}/sysstat ] && . ${SYSCONFIG_DIR}/sysstat
                                     ^----------------------^ SC1091 (info): Not following: ./sysstat was not specified as input (see shellcheck -x).


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 26:
if [ x$YESTERDAY = xno ]
     ^---------^ SC2268 (style): Avoid x-prefix in comparisons as it no longer serves a purpose.
      ^--------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
if [ "$YESTERDAY" = no ]


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 35:
	DATE=`date ${DATE_OPTS} +%Y%m%d`
             ^-------------------------^ SC2006 (style): Use $(...) notation instead of legacy backticks `...`.

Did you mean: 
	DATE=$(date ${DATE_OPTS} +%Y%m%d)


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 37:
	DATE=`date ${DATE_OPTS} +%d`
             ^---------------------^ SC2006 (style): Use $(...) notation instead of legacy backticks `...`.

Did you mean: 
	DATE=$(date ${DATE_OPTS} +%d)


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 47:
cd ${ENDIR}
^---------^ SC2164 (warning): Use 'cd ... || exit' or 'cd ... || return' in case cd fails.

Did you mean: 
cd ${ENDIR} || exit


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 48:
if [ x${REPORTS} != xfalse ]
      ^--------^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
if [ x"${REPORTS}" != xfalse ]


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 50:
	${ENDIR}/sar $* -f ${DFILE} > ${RPT}
                     ^-- SC2048 (warning): Use "$@" (with quotes) to prevent whitespace problems.
                     ^-- SC2086 (info): Double quote to prevent globbing and word splitting.
                           ^------^ SC2086 (info): Double quote to prevent globbing and word splitting.
                                      ^----^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
	${ENDIR}/sar "$*" -f "${DFILE}" > "${RPT}"


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 56:
	| egrep "${SAFILES_REGEX}" \
          ^---^ SC2196 (info): egrep is non-standard and deprecated. Use grep -E instead.


In /logs/firmware/unblob_extracted/firmware_extract/4325012-58052244.squashfs_v4_le_extract/usr/libexec/sa/sa2 line 62:
	| egrep "${UNCOMPRESSED_SAFILES_REGEX}" \
          ^---^ SC2196 (info): egrep is non-standard and deprecated. Use grep -E instead.

For more information:
  https://www.shellcheck.net/wiki/SC2034 -- exec_prefix appears unused. Verif...
  https://www.shellcheck.net/wiki/SC2048 -- Use "$@" (with quotes) to prevent...
  https://www.shellcheck.net/wiki/SC2164 -- Use 'cd ... || exit' or 'cd ... |...