shell - What is the difference between "<inp somecommand" and "somecommand <inp"? -


किसी भी यूनिक्स खोल पर, दोनों रूपों & lt; input.txt cat और cat & Lt; input.txt ठीक उसी तरह से काम करता है क्या उनके बीच कोई अंतर है?

नहीं, उनके बीच कोई अंतर नहीं है। देखें, जो एक साधारण आदेश के पहले या उसके बाद एक रीडायरेक्शन के बीच अंतर नहीं करता है (यौगिक आज्ञाओं के लिए, विनिर्देश केवल आवश्यक है कि अंत में शैल का समर्थन पुनर्निर्देशन)।

मनमाने बिंदुओं पर पुनर्निर्देशन के भीतर एक साधारण आदेश कुछ नहीं है जो POSIX sh विनिर्देशन को समर्थन की आवश्यकता होती है के लिये; हालांकि, ऐसे बाश जैसे गोले में जहां उन्हें अनुमति दी जाती है, ये भी वाक्यात्मक रूप से समतुल्य हैं।


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