4 ms·

For single files or monitoring other pipe based operations (like network transfers) pv [1] is also a useful tool. 1 - http://www.ivarch.com/programs/pv.shtml h

For single files or monitoring other pipe based operations (like network transfers) pv [1] is also a useful tool. 1 - http://www.ivarch.com/programs/pv.shtml http://www.ivarch.com/programs/pv.shtml

ollybee 13y ago
I find pv useful when moving MySQL databases between servers. mysqldump -u user dbname | pv | mysql -u user -h some_remote server dbname
baiitsu 13y ago
Using pv: gcp() { cat "$1" | pv | cat > "$2" }
- gcmalloc 13y ago
  useless use of cat pv < "$1" > "$2"
  - nitrogen 13y ago
    Even if the cat at the beginning of a pipe isn't strictly necessary, it still helps readability to have everything flowing from left to right.
    - emillon 13y ago
      I also advocate this "useless" use of cat, but you can write the redirection before the command: <"$1" pv >"$2"
    - michaelmior 13y ago
      The bigger problem is that using cat destroys the file size information.
  - nilved 13y ago
    pv reads content from a file by default, so that can actually be reduced further to: pv "$1" > "$2"
    - simcop2387 13y ago
      Which will actually give better results this way, since it'll read the size of the file and use that to provide an estimate even.
dexen 13y ago
to copy a tree of files: tar c SOURCE_DIR | pv | tar xv -C DEST_DIR or # on source computer tar c SOURCE_DIR | pv > /dev/tcp/192.168.1.2/4567 # on destination computer computer nc -l -p 4567 | pv | tar xv -C DEST_DIR
- nitrogen 13y ago
  For anyone curious as I was why the /dev/tcp/... redirection works, the Bash manual contains the following: Bash handles several filenames specially when they are used in redirections, as described in the following table: /dev/fd/fd If fd is a valid integer, file descriptor fd is duplicated. /dev/stdin File descriptor 0 is duplicated. /dev/stdout File descriptor 1 is duplicated. /dev/stderr File descriptor 2 is duplicated. /dev/tcp/host/port If host is a valid hostname or Internet address, and port is an integer port number or service name, bash attempts to open a TCP connection to the corresponding socket. /dev/udp/host/port If host is a valid hostname or Internet address, and port is an integer port number or service name, bash attempts to open a UDP connection to the corresponding socket.
michaelmior 13y ago
pv is a great tool and one of the first things I install on new machines. I hate having no idea how long an operation is going to take. For example, loading a SQL dump pv foo.sql | mysql

For single files or monitoring other pipe based operations (like network transfers) pv [1] is also a useful tool. 1 - http://www.ivarch.com/programs/pv.shtml http://www.ivarch.com/programs/pv.shtml

ollybee 13y ago

I find pv useful when moving MySQL databases between servers. mysqldump -u user dbname | pv | mysql -u user -h some_remote server dbname

baiitsu 13y ago

Using pv: gcp() { cat "$1" | pv | cat > "$2" }

gcmalloc 13y ago
useless use of cat pv < "$1" > "$2"
- nitrogen 13y ago
  Even if the cat at the beginning of a pipe isn't strictly necessary, it still helps readability to have everything flowing from left to right.
  - emillon 13y ago
    I also advocate this "useless" use of cat, but you can write the redirection before the command: <"$1" pv >"$2"
  - michaelmior 13y ago
    The bigger problem is that using cat destroys the file size information.
- nilved 13y ago
  pv reads content from a file by default, so that can actually be reduced further to: pv "$1" > "$2"
  - simcop2387 13y ago
    Which will actually give better results this way, since it'll read the size of the file and use that to provide an estimate even.

dexen 13y ago

nitrogen 13y ago
For anyone curious as I was why the /dev/tcp/... redirection works, the Bash manual contains the following: Bash handles several filenames specially when they are used in redirections, as described in the following table: /dev/fd/fd If fd is a valid integer, file descriptor fd is duplicated. /dev/stdin File descriptor 0 is duplicated. /dev/stdout File descriptor 1 is duplicated. /dev/stderr File descriptor 2 is duplicated. /dev/tcp/host/port If host is a valid hostname or Internet address, and port is an integer port number or service name, bash attempts to open a TCP connection to the corresponding socket. /dev/udp/host/port If host is a valid hostname or Internet address, and port is an integer port number or service name, bash attempts to open a UDP connection to the corresponding socket.

michaelmior 13y ago

pv is a great tool and one of the first things I install on new machines. I hate having no idea how long an operation is going to take. For example, loading a SQL dump pv foo.sql | mysql