我试图重新编码usertrustrsaaddtrustca.crt, Jan 31, 2019, trustedCertEntry,
Certificate fingerprint (SHA1): EA:B0:40:68:9A:0D:80:5B:5D:6F:D6:54:FC:16:8C:FF:00:B7:8B:E3
sectigorsadomainvalidationsecureserverca, Jan 31, 2019, trustedCertEntry,
Certificate fingerprint (SHA1): 33:E4:E8:08:07:20:4C:2B:61:82:A3:A1:4B:59:1A:CD:25:B5:F0:DB
af_ssl, Jan 31, 2019, PrivateKeyEntry,
Certificate fingerprint (SHA1): C8:C5:DA:2A:83:66:A3:DE:15:05:31:35:C4:35:FD:7F:DE:4F:DE:75
addtrustexternalcaroot, Jan 31, 2019, trustedCertEntry,
Certificate fingerprint (SHA1): 02:FA:F3:E2:91:43:54:68:60:78:57:69:4D:F5:E4:5B:68:85:18:68
计划（人LS）。如果ls没有参数，并且其输出将通过ls之类的管道重定向，则它将使用ls > file标志。
我必须使用哪个函数来查找输出重定向？