The shell's pci command was not written to read from standard input. It expects all its input on the command line.
I would say in general that if you execute a command and pass it no parameters, and it then prompts you in some way for input, then that command will likely accept input redirected from a file. If you execute pci without any parameters, it simply lists all the devices in the system and terminates, so it clearly is not prepared to read from standard input (or a redirected file). It is strictly up to whomever writes a program/command whether they do so in a manner that allows it to accept input from standard input. For example, I have written a grep utility for the shell that expects one or more filenames to search to be on the command line; however, if there are no filenames on the command line, the utility searches standard input. Regards, Jim -----Original Message----- From: edk2-devel [mailto:edk2-devel-boun...@lists.01.org] On Behalf Of Tiger Liu Sent: Thursday, September 21, 2017 1:11 AM To: edk2-devel@lists.01.org Subject: [edk2] Shell input redirection question Hi, experts: I have a question about input redirection in Shell environment. Take pci command as sample. I wrote a txt file(file name is : inputsample.txt), its content is: 00 00 01 -i 00 00 02 –i It means I just wanted to dump D0F1/D0F2’s config space. Then, I use this command sequence in shell : pci <a inputsample.txt But it seems not recognize this input file’s content. Why? Thanks best wishes, 保密声明： 本邮件含有保密或专有信息，仅供指定收件人使用。严禁对本邮件或其内容做任何未经授权的查阅、使用、复制或转发。 CONFIDENTIAL NOTE: This email contains confidential or legally privileged information and is for the sole use of its intended recipient. Any unauthorized review, use, copying or forwarding of this email or the content of this email is strictly prohibited. _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
