Phpexec () a shell result error occurs because grep in php can only process text streams, but binary streams cannot.

Cataa.txt | grep & amp; #39; startup & amp; #39; | wc-l can be tested in the linux command line. But the exec in php has a problem, which is strange. Result: the error message "cat: writeerror: Brokenpipe" indicates that the cat: writeerror is useless... "/> <script cat aa.txt | grep 'startup' | wc-l is available in linux command lines. But the exec in php has a problem, which is strange. Result: the following error message is displayed: cat: write error: Broken pipe has been exhausted. after checking a lot of information, the solution is finally solved. When the-a option is added to the grep option, the grep-a option indicates that Process a binary file as if it were text; this is equivalent to the -- binary-files = text option should be cat. the content of this file has a binary stream, causing grep to not recognize