python常用又记不住的方法

快速生成大文件

from tempfile import mkstemp
from neo_tool.n_file import fallocate
f = fallocate.Fallocate()
fd, tmp_file = mkstemp()
size = 1024
f(fd, 0, 0, size)

高效的零拷贝

from neo_tool.n_file import splice
s = splice.Splice()
r, w = os.pipe()
with open("/tmp/_splice.txt", "rb") as f:
    bytes_in_pipe, _1, _2 = s(f, None, w, None, 51, 0)
    with open("/tmp/_splice_w.txt", "wb") as wf:
        print(s(r, None, wf, None, 1024, 0))
        
s = splice.Tee()

md5 socket

from neo_tool.net.md5_socket import get_md5_socket
s = get_md5_socket()
os.write(s, "11111111211111111111")
hex_checksum = ''.join("%02x" % ord(c) for c in os.read(s, 16))
print(hex_checksum)