3.13 GFORTRAN_UNFORMATTED_BUFFER_SIZE—Set buffer size for unformatted I/O
The GFORTRAN_UNFORMATTED_BUFFER_SIZE environment variable specifies buffer size in bytes to be used for unformatted output. The default value is 131072.
© Free Software Foundation
Licensed under the GNU Free Documentation License, Version 1.3.
https://gcc.gnu.org/onlinedocs/gcc-11.1.0/gfortran/GFORTRAN_005fUNFORMATTED_005fBUFFER_005fSIZE.html