diff options
| -rw-r--r-- | txr.1 | 32 | ||||
| -rw-r--r-- | txr.c | 23 |
2 files changed, 54 insertions, 1 deletions
@@ -664,6 +664,12 @@ supports that behavior, or even that exact version. If the option is specified more than once, the behavior is not specified. +Compatibility can also be requested via the +.code TXR_COMPAT +environment variable instead of the +.code -C +option. + For more information, see the COMPATIBILITY section. .meIP >> --gc-delta= number @@ -37894,7 +37900,31 @@ option can be used to request emulation of old behavior. The option was introduced in \*(TX 98, and so the oldest \*(TX version which can be emulated is \*(TX 97. -Here are version values which have a special meaning as arguments to the +Side effects occur in the processing of the option. If the option is specified +multiple times, the behavior is unspecified. + +.coNP Environment variable @ TXR_COMPAT + +If the +.code TXR_COMPAT +environment variable exists, and its value is not en empty string, +it must contain a decimal integer. Its value is taken by \*(TX as a request +to emulate old behaviors, just like the value of the +.code -C +option. + +If the variable has incorrect contents or an out-of-range value, +\*(TX will print an error diagnostic and exit. + +If both +.code -C +and the +.code TXR_COMPAT +environment variable are supplied, the behavior is unspecified. + +.coNP Compatibility Version Values + +The following version values which have a special meaning as arguments to the .code -C option, along with a description of what behaviors are affected. For each of these version values, the described behaviors are provided if @@ -54,6 +54,7 @@ #include "regex.h" #include "arith.h" #include "lisplib.h" +#include "sysif.h" #include "txr.h" const wchli_t *version = wli(TXR_VER); @@ -413,10 +414,27 @@ int txr_main(int argc, char **argv) val enter_repl = nil; val args_s = intern(lit("*args*"), user_package); val self_path_s = intern(lit("self-path"), user_package); + val compat_var = lit("TXR_COMPAT"); + val compat_val = getenv_wrap(compat_var); list_collect_decl(arg_list, arg_tail); setvbuf(stderr, 0, _IOLBF, 0); + if (compat_val && length(compat_val) != zero) { + val value = int_str(compat_val, nil); + if (!value) { + format(std_error, + lit("~a: environment variable ~a=~a must be decimal integer\n"), + prog_string, compat_var, compat_val, nao); + return EXIT_FAILURE; + } + if (!compat(value)) { + format(std_error, lit("~a: caused by environment variable ~a=~a\n"), + prog_string, compat_var, compat_val, nao); + return EXIT_FAILURE; + } + } + if (argc <= 1) { #if HAVE_TERMIOS banner(); @@ -792,6 +810,11 @@ int txr_main(int argc, char **argv) repl: #if HAVE_TERMIOS + if (compat_val) + format(std_output, + lit("Note: operating in TXR ~a compatibility mode " + "due to environment variable.\n"), + num(opt_compat), nao); repl(bindings, std_input, std_output); #endif return 0; |