On Thu, 23 May 2019 13:45:02 -0400, Jude DaShiell said:
echo "first available message:" scan -width 6|head -1
scan -width 6 first will be much faster.
echo "last available message:" scan -width 6|tail -1
scan -width 6 last will be much faster.
If you have 10,000 entries in a folder, scan first/last still has to read and
sort the directory, but it can find first and last without opening a file.
A quick test:
[~] strace -f scan -width 6 +inbox 2>| /tmp/inbox | head -1
1
[~] grep open /tmp/inbox | tail -1
openat(AT_FDCWD, "1171", O_RDONLY) = 3
Yes, it reads that many files before the back-pressure SIGPIPE from 'head -1'
exiting catches up with it.
scan | tail will have to open and read all 10,000 files.....
pgpYKsJR_n8a5.pgp
Description: PGP signature
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