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Chris Davies
Chris Davies
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I'd suggest you simplify the construct and give the next person reading the code a chance to see what's going on. Your main issue is that you seem to be confusing your indirect execution $( ... ) with [ ... ] as a test operator. Apologies if I've misunderstood the flow, but I think this is what you intend:

# Count files on the remote system and confirm that there is at least one
DATE7=$(date -v -7d '+%Y%m%d')
NFILES=$(ssh [email protected] "ls -d '/snapshots/$DATE7'* 2> /dev/null | wc -l")

# If the ssh worked and we have found files then archive them
if [ $? -eq 0 && 0 -lt $NFILES ]
then
    # Archive the files
    ssh [email protected] "
        tar -czf '$ARCHIVES_DIR/$YESTERDAY.tar.gz' '$SNAPSHOT_DIR/$YESTERDAY'* &&
        rm -rf '$SNAPSHOT_DIR/$YESTERDAY'
    "
fi

This supposes that ARCHIVES_DIR, SNAPSHOT_DIR and YESTERDAY are defined locally elsewhere in your script.

Remember that "..." will interpolate variables' values immediately, whereas '...' will treat text such as $WIDGET as a literal seven character string starting with a dollar symbol. This is important to note given I have got sequences like " '...' " and ' "..." ' in this code.

I'd suggest you simplify the construct and give the next person reading the code a chance to see what's going on. Your main issue is that you seem to be confusing your indirect execution $( ... ) with [ ... ] as a test operator. Apologies if I've misunderstood the flow, but I think this is what you intend:

# Count files on the remote system and confirm that there is at least one
DATE7=$(date -v -7d '+%Y%m%d')
NFILES=$(ssh [email protected] "ls -d '/snapshots/$DATE7'* 2> /dev/null | wc -l")

if [ $? -eq 0 && 0 -lt $NFILES ]
then
    # Archive the files
    ssh [email protected] "
        tar -czf '$ARCHIVES_DIR/$YESTERDAY.tar.gz' '$SNAPSHOT_DIR/$YESTERDAY'* &&
        rm -rf '$SNAPSHOT_DIR/$YESTERDAY'
    "
fi

This supposes that ARCHIVES_DIR, SNAPSHOT_DIR and YESTERDAY are defined locally elsewhere in your script.

Remember that "..." will interpolate variables' values immediately, whereas '...' will treat text such as $WIDGET as a literal seven character string starting with a dollar symbol. This is important to note given I have got sequences like " '...' " and ' "..." ' in this code.

I'd suggest you simplify the construct and give the next person reading the code a chance to see what's going on. Your main issue is that you seem to be confusing your indirect execution $( ... ) with [ ... ] as a test operator. Apologies if I've misunderstood the flow, but I think this is what you intend:

# Count files on the remote system and confirm that there is at least one
DATE7=$(date -v -7d '+%Y%m%d')
NFILES=$(ssh [email protected] "ls -d '/snapshots/$DATE7'* 2> /dev/null | wc -l")

# If the ssh worked and we have found files then archive them
if [ $? -eq 0 && 0 -lt $NFILES ]
then
    # Archive the files
    ssh [email protected] "
        tar -czf '$ARCHIVES_DIR/$YESTERDAY.tar.gz' '$SNAPSHOT_DIR/$YESTERDAY'* &&
        rm -rf '$SNAPSHOT_DIR/$YESTERDAY'
    "
fi

This supposes that ARCHIVES_DIR, SNAPSHOT_DIR and YESTERDAY are defined locally elsewhere in your script.

Remember that "..." will interpolate variables' values immediately, whereas '...' will treat text such as $WIDGET as a literal seven character string starting with a dollar symbol. This is important to note given I have got sequences like " '...' " and ' "..." ' in this code.

Source Link
Chris Davies
Chris Davies
  • 128.2k
  • 16
  • 179
  • 324

I'd suggest you simplify the construct and give the next person reading the code a chance to see what's going on. Your main issue is that you seem to be confusing your indirect execution $( ... ) with [ ... ] as a test operator. Apologies if I've misunderstood the flow, but I think this is what you intend:

# Count files on the remote system and confirm that there is at least one
DATE7=$(date -v -7d '+%Y%m%d')
NFILES=$(ssh [email protected] "ls -d '/snapshots/$DATE7'* 2> /dev/null | wc -l")

if [ $? -eq 0 && 0 -lt $NFILES ]
then
    # Archive the files
    ssh [email protected] "
        tar -czf '$ARCHIVES_DIR/$YESTERDAY.tar.gz' '$SNAPSHOT_DIR/$YESTERDAY'* &&
        rm -rf '$SNAPSHOT_DIR/$YESTERDAY'
    "
fi

This supposes that ARCHIVES_DIR, SNAPSHOT_DIR and YESTERDAY are defined locally elsewhere in your script.

Remember that "..." will interpolate variables' values immediately, whereas '...' will treat text such as $WIDGET as a literal seven character string starting with a dollar symbol. This is important to note given I have got sequences like " '...' " and ' "..." ' in this code.