For the sake of portability, most X-PLOR files are ASCII files. The record length of the ASCII is not more than 132 characters. One exception to this rule is the trajectory file (specified by the ``TRAJectory=<filename> ISVFrq=<integer>" keywords, Section 10.1.6). This file is a binary file that can be converted to an ASCII file and vice versa by the dynamics merge statement. The use of ASCII files greatly simplifies communication between various types of computer equipment (workstations, minicomputers, supercomputers, etc.).
X-PLOR script files are free-field ASCII files with variable record length. The maximum record length is determined by the internal parameter COMMAX (Section 22.2), which defaults to 132 characters. The command file can be assigned to an interactive terminal. In this case, the user types the X-PLOR statements interactively.