IOINIT(3F) IOINIT(3F) NAME ioinit - change f77 I/O initialization SYNOPSIS logical function ioinit (cctl, bzro, apnd, prefix, vrbose) logical cctl, bzro, apnd, vrbose character*(*) prefix DESCRIPTION This routine will initialize several global parameters in the f77 I/O system, and attach externally defined files to logical units at run time. The effect of the flag arguments applies to logical units opened after _i_o_i_n_i_t is called. The exception is the preassigned units, 5 and 6, to which _c_c_t_l and _b_z_r_o will apply at any time. _I_o_i_n_i_t is written in Fortran-77. By default, carriage control is not recognized on any logical unit. If _c_c_t_l is .true. then carriage control will be recognized on formatted output to all logical units except unit 0, the diagnostic channel. Otherwise the default will be restored. By default, trailing and embedded blanks in input data fields are ignored. If _b_z_r_o is .true. then such blanks will be treated as zeros. Otherwise the default will be restored. By default, all files opened for sequential access are positioned at their beginning. It is sometimes necessary or convenient to open at the END-OF-FILE so that a write will append to the existing data. If _a_p_n_d is .true. then files opened subsequently on any logical unit will be positioned at their end upon opening. A value of .false. will restore the default behavior. _I_o_i_n_i_t may be used to associate file names with Fortran logical unit numbers through environment variables (see "Introduction to the f77 I/O Library" for a more general way of doing this). If the argument _p_r_e_f_i_x is a non-blank string, then names of the form prefixNN will be sought in the program environment. The value associated with each such name found will be used to open logical unit NN for formatted sequential access. For example, if f77 program _m_y_p_r_o_g_r_a_m included the call call ioinit (.true., .false., .false., ′FORT′, .false.) then when the following sequence % setenv FORT01 mydata % setenv FORT12 myresults % myprogram would result in logical unit 1 opened to file _m_y_d_a_t_a and logical unit 12 opened to file _m_y_r_e_s_u_l_t_s. Both files would be positioned at their beginning. Any formatted output would have column 1 removed and inter‐ preted as carriage control. Embedded and trailing blanks would be ignored on input. If the argument _v_r_b_o_s_e is .true. then _i_o_i_n_i_t will report on its activ‐ ity. The effect of call ioinit (.true., .true., .false., ′′, .false.) can be achieved without the actual call by including ‘‘-lI66’’ on the _f_7_7 command line. This gives carriage control on all logical units except 0, causes files to be opened at their beginning, and causes blanks to be interpreted as zero’s. The internal flags are stored in a labeled common block with the fol‐ lowing definition: integer*2 ieof, ictl, ibzr common /ioiflg/ ieof, ictl, ibzr FILES /usr/lib/libI77.a f77 I/O library /usr/lib/libI66.a sets older fortran I/O modes SEE ALSO getarg(3F), getenv(3F), ‘‘Introduction to the f77 I/O Library’’ BUGS _P_r_e_f_i_x can be no longer than 30 characters. A pathname associated with an environment name can be no longer than 255 characters. The ‘‘+’’ carriage control does not work. 4.2 Berkeley Distribution May 27, 1986 IOINIT(3F)