如何将A的标准输出重定向到B的标准输入并将B的标准输出重定向到A的标准输入?

时间:2019-05-26 01:55:45

标签: bash io-redirection

现在我有程序A和B。我想使用bash将A的标准输出重定向到B的标准输入,并将B的标准输出重定向到A的标准输入。

我看到有人在做this,但他们没有解释他们是如何做到的。

有什么建议吗?


Upd:我找到了可以完成此任务的脚本,但我不明白为什么:

{ ./A < /dev/fd/3 | ./B 3>&-; } 3>&1 | :

1 个答案:

答案 0 :(得分:2)

您可以使用CREATE OR REPLACE TRIGGER FLIGHT_BIU BEFORE INSERT OR UPDATE ON FLIGHT FOR EACH ROW DECLARE strMAX_PILOTYESNO STAFF.PILOTYESNO%TYPE; BEGIN SELECT MAX(UPPER(PILOTYESNO)) INTO strMAX_PILOTYESNO FROM STAFF WHERE STAFFID IN (:NEW.CAPTAINSTAFFID, :NEW.FIRSTOFFICERSTAFFID); IF strMAX_PILOTYESNO = 'N' THEN RAISE_APPLICATION_ERROR(-20000, 'No pilot assigned to the flight'); END IF; -- Add code here to handle QUALIFICATION, wherever that may be found END FLIGHT_BIU; / 实用程序。它将把任何东西连接起来,包括彼此之间的两个过程:

      str_category = "category"
      File_inspecies = open("C:/Users/Laura/Desktop/species_taxon.csv", "r")
     csv_inspecies = csv.DictReader(File_inspecies)
     str_species = "species"
     str_taxon = "taxon"

    class species:
    _cls_str_species_name = ""
    _cls_str_taxon = ""

    def _init_(self, name, species):
    self._cls_str_name = name
    self._cls_str_species = species

    str_species = {species}
    first_str_species_name = []

    for first_cols in csv_inspecies:
    file_inspecies =        str_species(first_cols[str_species],first_cols[str_taxon])
    pub_1st_obj_species.append(inspecies)
    first_str_species_name.append(inspecies.get_species_name())

    File_inspecies.close()