curl 和 Wget 的比较

from:
http://daniel.haxx.se/docs/curl-vs-wget.html


curl vs Wget

This document started off as a blog entry, but I decided that I should better make a permanent home for this as I'm sure I'll get reasons to update and fix this as time goes by.

The main differences as I see them. Please consider my bias towards curl since after all, curl is my baby - but I have contributed code to Wget as well.

Please let me know if you have other thoughts or comments on this document. Email them to me or reply on the blog entry.

curl

• Features and is powered by libcurl - a cross-platform library with a stable API that can be used by each and everyone. This difference is major since it creates a completely different attitude on how to do things internally. It is also slightly harder to make a library than a "mere" command line tool.
• Pipes. curl is more in the traditional unix-style, it sends more stuff to stdout, and reads more from stdin in a "everything is a pipe" manner.
• Return codes. curl returns a range of defined and documented return codes for various (error) situations.
• Single shot. curl is basically made to do single-shot transfers of data. It transfers just the URLs that the user specifies, and does not contain any recursive downloading logic nor any sort of HTML parser.
• More protocols. curl supports FTP, FTPS, HTTP, HTTPS, SCP, SFTP, TFTP, TELNET, DICT, LDAP, LDAPS and FILE at the time of this writing. Wget supports HTTP, HTTPS and FTP.
• More portable. Ironically curl builds and runs on lots of more platforms than wget, in spite of their attempts to keep things conservative. For example: OS/400, TPF and other more "exotic" platforms that aren't straight-forward unix clones.
• More SSL libraries and SSL support. curl can be built with one out of four different SSL/TLS libraries, and it offers more control and wider support for protocol details.
• curl (or rather libcurl) supports more HTTP authentication methods, and especially when you try over HTTP proxies.
• Bidirectional. curl offers upload and sending capabilities. Wget only offers plain HTTP POST support.
• HTTP multipart/form-data sending, which allows users to do HTTP "upload" and in general emulate browsers and do HTTP automation to a wider extent
• Compression. curl supports gzip and inflate Content-Encoding and does automatic decompression.

Wget

• Wget is command line only. There's no lib or anything.
• Recursive! Wget's major strong side compared to curl is its ability to download recursively, or even just download everything that is referred to from a remote resource, be it a HTML page or a FTP directory listing.
• Older. Wget has traces back to 1995, while curl can be tracked back no longer than 1997.
• Less developer activity. While this can be debated, I consider three metrics here: mailing list activity, source code commit frequency and release frequency. Anyone following these two projects can see that the curl project has a lot higher pace in all these areas, and it has indeed been so for several years.
• HTTP 1.0. Wget still does its HTTP operations using HTTP 1.0, and while that is still working remarkably fine and hardly ever is troublesome to the end-users, it is still a fact. curl has done HTTP 1.1 since March 2001 (while still offering optional 1.0 requests).
• GPL. Wget is 100% GPL v3. curl is MIT licensed.
• GNU. Wget is part of the GNU project and all copyrights are assigned to FSF. The curl project is entirely stand-alone and independent with no organization parenting at all - with almost all copyrights owned by Daniel.
• Wget requires no extra options to simply download a remote URL to a local file, while curl requires -o or -O. However trivial, this fact is often mentioned to me when people explain why they prefer downloading with wget.

Additional Stuff

You may argue that I should compare uploading capabilities with wput, but that's a separate tool and I don't include that in this comparison.

For a stricter feature by feature comparison (that also compares other similar tools), see the curl comparison table

Thanks

Feedback and improvements by: Micah Cowan, Olemis Lang

Updated: June 4, 2009 23:07 (Central European, Stockholm Sweden)