I'm using the following statement (simplified version):

tail -f -c+1 <filename>

in order to pipe a file to a process.

What I've found, though, is that there is a number of lines at the end which are not piped.

A specific example is piping a mysql file, and stopping when the end is reached:

tail -f -c+0 mysqdump.sql | sed '/^-- Dump completed/ q0'

This doesn't work - the last line of the dump -- Dump completed [...] is not piped to sed.

My guess is that the tail -f buffer, in this case, is flushed only when it's full.

Does anybody know how can I workaround this?

I'm using the following statement (simplified version):

tail -f -c+1 <filename>

in order to pipe a file to a process.

What I've found, though, is that there is a number of lines at the end which are not piped.

A specific example is piping a mysql file, and stopping when the end is reached:

tail -f -c+1 mysqdump.sql | sed '/^-- Dump completed/ q0'

This doesn't work - the last line of the dump -- Dump completed [...] is not piped to sed.

My guess is that the tail -f buffer, in this case, is flushed only when it's full.

Does anybody know how can I workaround this?

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I've found the cause - the description is not complete (and the code doesn't exhibit the behavior).

The problem happens when piping from a compressed (lzma) file:

tail -f -c+1 <filename.lzma> | lzma -d | sed '/^-- Dump completed/ q0'

Most likely, tail is not sending the last compressed block, because it doesn't detect any new line, as the input is binary.

I'm using the following statement (simplified version):

tail -f -c+1 <filename>

in order to pipe a file to a process.

What I've found though, is that there is a number of lines at the end, which are not piped.

A specific example is piping a mysql file, and stopping when the end is reached:

tail -f -c+0 mysqdump.sql | sed '/^-- Dump completed/ q0'

This doesn't work - the last line of the dump, "-- Dump completed [...]" is not piped to sed.

My guess is that the tail -f buffer, in this case, is flushed only when it's full.

Does anybody know how can I workaround this?

I'm using the following statement (simplified version):

tail -f -c+1 <filename>

in order to pipe a file to a process.

What I've found, though, is that there is a number of lines at the end which are not piped.

A specific example is piping a mysql file, and stopping when the end is reached:

tail -f -c+0 mysqdump.sql | sed '/^-- Dump completed/ q0'

This doesn't work - the last line of the dump -- Dump completed [...] is not piped to sed.

My guess is that the tail -f buffer, in this case, is flushed only when it's full.

Does anybody know how can I workaround this?