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author | Karl Berry <karl@freefriends.org> | 2021-02-25 19:22:25 +0000 |
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committer | Karl Berry <karl@freefriends.org> | 2021-02-25 19:22:25 +0000 |
commit | ad547a6b5986815fda458221149728d9d9ab1d87 (patch) | |
tree | 16296910eb3eca724371474ea9aea3994dc69614 /Build/source/texk/kpathsea/putenv.c | |
parent | 947b43de3dd21d58ccc2ffadefc4441ea1c2a813 (diff) |
restore Build,TODO from r57911
git-svn-id: svn://tug.org/texlive/trunk@57915 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/texk/kpathsea/putenv.c')
-rw-r--r-- | Build/source/texk/kpathsea/putenv.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/Build/source/texk/kpathsea/putenv.c b/Build/source/texk/kpathsea/putenv.c new file mode 100644 index 00000000000..34cbd3add89 --- /dev/null +++ b/Build/source/texk/kpathsea/putenv.c @@ -0,0 +1,110 @@ +/****************************************************************/ +/* */ +/* putenv(3) */ +/* */ +/* Change or add an environment entry */ +/* */ +/****************************************************************/ +/* origination 1987-Oct-7 T. Holm */ +/****************************************************************/ + +/* +Path: hoptoad!pacbell!ames!ll-xn!mit-eddie!uw-beaver!ssc-vax!uvicctr!tholm +From: tholm@uvicctr.UUCP (Terrence W. Holm) +Newsgroups: comp.os.minix +Subject: putenv(3) +Message-ID: <395@uvicctr.UUCP> +Date: 5 May 88 06:40:52 GMT +Organization: University of Victoria, Victoria B.C. Canada + +EFTH Minix report #2 - May 1988 - putenv(3) + +This is an implementation of putenv(3) that we +wrote for Minix. Please consider this a public +domain program. +*/ + +#define NULL 0 +#define PSIZE sizeof(char *) + +extern char **environ; + +char *strchr(); +char *malloc(); + +/****************************************************************/ +/* */ +/* int */ +/* putenv( entry ) */ +/* */ +/* The "entry" should follow the form */ +/* "NAME=VALUE". This routine will search the */ +/* user environment for "NAME" and replace its */ +/* value with "VALUE". */ +/* */ +/* Note that "entry" is not copied, it is used */ +/* as the environment entry. This means that it */ +/* must not be unallocated or otherwise modifed */ +/* by the caller, unless it is replaced by a */ +/* subsequent putenv(). */ +/* */ +/* If the name is not found in the environment, */ +/* then a new vector of pointers is allocated, */ +/* "entry" is put at the end and the global */ +/* variable "environ" is updated. */ +/* */ +/* This function normally returns 0, but -1 */ +/* is returned if it can not allocate enough */ +/* space using malloc(3), or "entry" does not */ +/* contain a '='. */ +/* */ +/****************************************************************/ + + +int +putenv( entry ) + char *entry; +{ + unsigned length; + unsigned size; + char *temp; + char **p; + char **new_environ; + + /* Find the length of the "NAME=" */ + + temp = strchr(entry,'='); + if ( temp == 0 ) + return( -1 ); + + length = (unsigned) (temp - entry + 1); + + + /* Scan through the environment looking for "NAME=" */ + + for ( p=environ; *p != 0 ; p++ ) + if ( strncmp( entry, *p, length ) == 0 ) + { + *p = entry; + return( 0 ); + } + + + /* The name was not found, build a bigger environment */ + + size = p - environ; + + new_environ = (char **) malloc( (size+2)*PSIZE ); + + if ( new_environ == (char **) NULL ) + return( -1 ); + + memcpy ((char *) new_environ, (char *) environ, size*PSIZE ); + + new_environ[size] = entry; + new_environ[size+1] = NULL; + + environ = new_environ; + + return(0); +} |