問題描述

我正在嘗試使用 Python 和 ftplib 從 z/os PDS 自動下載一些文本文件.

I'm trying to automate downloading of some text files from a z/os PDS, using Python and ftplib.

由于主機文件是 EBCDIC，我不能簡單地使用 FTP.retrbinary().

Since the host files are EBCDIC, I can't simply use FTP.retrbinary().

FTP.retrlines()，當與 open(file,w).writelines 作為回調(diào)一起使用時，當然不提供 EOL.

FTP.retrlines(), when used with open(file,w).writelines as its callback, doesn't, of course, provide EOLs.

所以，對于初學者來說，我想出了這段對我來說看起來不錯"的代碼，但由于我是一個相對的 Python 菜鳥，任何人都可以提出更好的方法嗎?顯然，為了讓這個問題保持簡單，這不是最終的花里胡哨的事情.

So, for starters, I've come up with this piece of code which "looks OK to me", but as I'm a relative Python noob, can anyone suggest a better approach? Obviously, to keep this question simple, this isn't the final, bells-and-whistles thing.

非常感謝.

#!python.exe
from ftplib import FTP

class xfile (file):
    def writelineswitheol(self, sequence):
        for s in sequence:
            self.write(s+"
")

sess = FTP("zos.server.to.be", "myid", "mypassword")
sess.sendcmd("site sbd=(IBM-1047,ISO8859-1)")
sess.cwd("'FOO.BAR.PDS'")
a = sess.nlst("RTB*")
for i in a:
    sess.retrlines("RETR "+i, xfile(i, 'w').writelineswitheol)
sess.quit()

更新:Python 3.0，平臺為 Windows XP 下的 MingW.

Update: Python 3.0, platform is MingW under Windows XP.

z/os PDS 具有固定的記錄結(jié)構(gòu)，而不是依賴行結(jié)尾作為記錄分隔符.但是，z/os FTP 服務(wù)器在以文本模式傳輸時，會提供記錄結(jié)尾，而 retrlines() 會去掉這些結(jié)尾.

z/os PDSs have a fixed record structure, rather than relying on line endings as record separators. However, the z/os FTP server, when transmitting in text mode, provides the record endings, which retrlines() strips off.

結(jié)束更新:

這是我修改后的解決方案，它將成為持續(xù)開發(fā)的基礎(chǔ)(例如，刪除內(nèi)置密碼):

Here's my revised solution, which will be the basis for ongoing development (removing built-in passwords, for example):

import ftplib
import os
from sys import exc_info

sess = ftplib.FTP("undisclosed.server.com", "userid", "password")
sess.sendcmd("site sbd=(IBM-1047,ISO8859-1)")
for dir in ["ASM", "ASML", "ASMM", "C", "CPP", "DLLA", "DLLC", "DLMC", "GEN", "HDR", "MAC"]:
    sess.cwd("'ZLTALM.PREP.%s'" % dir)
    try:
        filelist = sess.nlst()
    except ftplib.error_perm as x:
        if (x.args[0][:3] != '550'):
            raise
    else:
        try:
            os.mkdir(dir)
        except:
            continue
        for hostfile in filelist:
            lines = []
            sess.retrlines("RETR "+hostfile, lines.append)
            pcfile = open("%s/%s"% (dir,hostfile), 'w')
            for line in lines:
                pcfile.write(line+"
")
            pcfile.close()
        print ("Done: " + dir)
sess.quit()

感謝 John 和 Vinay

My thanks to both John and Vinay

推薦答案

我在試圖弄清楚如何從 z/OS 遞歸下載數(shù)據(jù)集時遇到了這個問題.多年來，我一直在使用簡單的 python 腳本從大型機下載 ebcdic 文件.它實際上就是這樣做的:

Just came across this question as I was trying to figure out how to recursively download datasets from z/OS. I've been using a simple python script for years now to download ebcdic files from the mainframe. It effectively just does this:

def writeline(line):
    file.write(line + "
")

file = open(filename, "w")
ftp.retrlines("retr " + filename, writeline)

這篇關(guān)于使用 Python 和 ftplib.FTP 從 z/os 下載文本文件的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！