Method for accessing file system of smart card through application module

Abstract

The application discloses a method for accessing a file system of a smart card through an application module, which is applied to smart cards. In the method, when a basic file selection instruction sent by an external terminal is executed by the application module of the smart card, a directory file, which corresponds to a target basic file, in the file system of the application module is first selected, so that a file access handle in the smart card points to the directory file, consequently, the target basic file located under the directory file can be selected, the circumstance of file access conflict which is caused when a file is directly selected under the premise that the file access handle possibly points to an unexpected file is prevented, and thereby the problem of file access conflict which can take place when the external terminal selects a file in the file system of the smart card through the application module is solved.

Description

technical field [0001] The invention relates to the technical field of smart card file systems, in particular to a method for accessing a smart card file system through an application module. Background technique [0002] Today, with the development of the communication era and intelligent life, the application scope of smart cards such as SIM (SIM, Subscriber Identity Module, subscriber identity module) cards and USIM (Universal Subscriber Identity Module, global subscriber identity module) cards is more and more widely. [0003] The file management in the smart card is realized by building the smart card file system. When the off-card terminal accesses the files in the smart card file system, it needs to use the only one file access handle in the smart card to expand the access operation. Here When the file access handle points to the target file to be accessed, the off-card terminal can perform corresponding access operations on the target file. [0004] Common file ope...

AI Technical Summary

Problems solved by technology

After the first off-card terminal selects an application module through a logical channel in the smart card, and before the application module prepares to perform file selection or read and write operations on a certain target basic file under the corresponding directory file, it may There is a second off-card terminal that accesses files other than the above-mentioned target basic file through other logical channels, resulting in the file access handle not pointing to the above-mentioned target basic file. At this time, if the above-mentioned application module insists on trying to select Or read and write operations, then obviously the expected file cannot be selected or read and written, thus causing a file access violation

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